The collection of a video format for the Sony a7IV hinges on the supposed use of the footage, obtainable cupboard space, and post-production workflow issues. This dedication impacts picture high quality, enhancing flexibility, and remaining supply choices. The phrase “what format ought to i shoot video sony a7iv” represents a standard inquiry amongst customers in search of optimum settings for his or her particular wants.
Selecting the suitable recording format is essential for maximizing the digital camera’s capabilities and guaranteeing environment friendly workflow. Incorrect format choice can result in compromised picture high quality, issue in enhancing, and compatibility points with numerous platforms. Understanding the nuances of every obtainable codec and backbone permits videographers to steadiness artistic imaginative and prescient with sensible necessities.
The next sections will discover the assorted video recording choices obtainable on the Sony a7IV, offering an in depth overview of their respective strengths and weaknesses. This can allow knowledgeable selections relating to decision, body charges, codecs, and colour profiles, guaranteeing optimum outcomes for a various vary of video tasks.
1. Decision
Decision, within the context of “what format ought to I shoot video Sony a7IV,” dictates the extent of element captured in every body of video. It straight impacts the readability, sharpness, and total visible high quality of the ultimate product. The selection of decision is a basic choice influencing storage necessities, processing energy wanted for enhancing, and suitability for various distribution platforms.
-
4K (UHD) Decision
The Sony a7IV presents 4K (UHD) decision, usually 3840 x 2160 pixels. This offers a excessive degree of element appropriate for skilled functions, bigger shows, and conditions the place cropping or reframing in post-production is important. Taking pictures in 4K ends in bigger file sizes, requiring extra cupboard space and demanding extra processing energy for enhancing.
-
1080p (Full HD) Decision
Alternatively, 1080p (Full HD) decision, at 1920 x 1080 pixels, presents a smaller file measurement and diminished processing calls for in comparison with 4K. That is applicable for tasks the place final element shouldn’t be important, equivalent to on-line content material, social media movies, or conditions the place cupboard space is proscribed. Whereas much less detailed than 4K, 1080p can nonetheless present wonderful visible high quality when correctly executed.
-
Cropping and Submit-Manufacturing Flexibility
Taking pictures in a better decision, equivalent to 4K, offers better flexibility in post-production. The additional element permits for cropping, reframing, and stabilizing footage with out vital lack of high quality. This may be advantageous for correcting errors, creating dynamic compositions, or adapting footage for various side ratios.
-
Show and Distribution Concerns
The supposed show medium and distribution platform additionally affect the selection of decision. If the ultimate video will primarily be seen on 4K shows, capturing in 4K maximizes visible influence. Nevertheless, if the audience is primarily viewing on smaller screens or platforms with bandwidth limitations, 1080p could also be a extra sensible alternative to cut back file sizes and guarantee clean playback.
Deciding on the suitable decision on the Sony a7IV requires a balanced consideration of element necessities, storage capability, processing energy, and audience. Taking pictures in 4K presents most flexibility and element however calls for extra assets, whereas 1080p offers a extra environment friendly possibility for much less demanding functions. Finally, the optimum decision is determined by the precise wants and targets of the video challenge.
2. Body Charge
Body charge, measured in frames per second (fps), essentially shapes the perceived movement and fluidity of video footage. Inside the context of “what format ought to I shoot video Sony a7IV,” it represents an important ingredient dictating the aesthetic and sensible functions of the recorded materials. A decrease body charge, equivalent to 24fps, usually imparts a cinematic aesthetic because of its affiliation with conventional movie. Conversely, greater body charges, equivalent to 60fps or 120fps, enable for clean slow-motion results throughout post-production, capturing fast-paced motion with better readability.
The interaction between body charge and different recording settings on the Sony a7IV is important. As an example, capturing at 60fps in 4K requires extra processing energy and cupboard space in comparison with capturing at 24fps in 1080p. Actual-world situations spotlight these trade-offs: Documentaries or narrative movies usually make the most of 24fps or 30fps to take care of a selected visible fashion. Sports activities videography or wildlife documentaries ceaselessly make use of greater body charges to seize element in fast-moving topics, enabling slow-motion evaluation or replays. Understanding this relationship permits customers to prioritize both visible aesthetics or sensible wants based mostly on the challenge’s necessities.
Deciding on the suitable body charge on the Sony a7IV entails contemplating the specified visible fashion, the character of the topic being recorded, and the restrictions of storage and processing capabilities. Improper body charge choice can result in movement artifacts, unnatural-looking footage, or extreme file sizes. Due to this fact, an intensive evaluation of those components is crucial to maximise the digital camera’s potential and make sure the remaining video meets the supposed aims, forming a core part of the broader choice relating to “what format ought to I shoot video Sony a7IV.”
3. Codec
The selection of codec is an integral a part of figuring out the optimum video format for the Sony a7IV. A codec, brief for “coder-decoder,” is an algorithm used to compress and decompress video information. It straight impacts file measurement, picture high quality, and enhancing workflow. Deciding on the suitable codec balances storage effectivity with the preservation of visible info, an important choice in answering “what format ought to i shoot video sony a7iv.”
-
XAVC S
XAVC S is a broadly used codec on the Sony a7IV, recognized for its steadiness between picture high quality and file measurement. It employs H.264 compression, a mature and environment friendly customary supported by most enhancing software program. XAVC S is appropriate for a variety of functions, from basic video recording to skilled tasks, providing a great compromise for customers prioritizing compatibility and ease of use. Instance: Recording interviews, documentaries, or occasion protection.
-
XAVC HS
XAVC HS makes use of H.265 (HEVC) compression, a extra superior codec that gives improved compression effectivity in comparison with H.264. This implies XAVC HS can obtain comparable picture high quality to XAVC S with smaller file sizes, or greater picture high quality with comparable file sizes. Nevertheless, H.265 requires extra processing energy for encoding and decoding, probably impacting enhancing efficiency on older computer systems. Instance: Taking pictures 4K footage for tasks the place file measurement is a main concern or when aiming for the very best attainable picture high quality inside storage constraints.
-
All-Intra (XAVC-I)
All-Intra codecs, equivalent to XAVC-I, compress every body individually, leading to considerably greater bitrates and bigger file sizes in comparison with inter-frame codecs like XAVC S and XAVC HS. This reduces the processing load throughout enhancing, providing smoother playback and quicker rendering instances, particularly with advanced edits or high-resolution footage. Instance: Skilled movie tasks, commercials, or any situation demanding the very best degree of enhancing efficiency and picture high quality with out compromise.
-
Proxy Recording
The Sony a7IV helps proxy recording, the place lower-resolution, lower-bitrate variations of the footage are created alongside the full-resolution information. These proxy information can be utilized for enhancing, decreasing the processing calls for on the pc. As soon as the enhancing is full, the challenge might be linked again to the unique full-resolution information for remaining rendering. This workflow is especially helpful when working with 4K or greater decision footage on much less highly effective computer systems. Instance: Function movie manufacturing, long-form documentaries, or any challenge involving intensive enhancing of high-resolution materials.
Understanding the traits of every codec and its influence on file measurement, picture high quality, and enhancing workflow is crucial for making knowledgeable selections about video format choice on the Sony a7IV. The selection between XAVC S, XAVC HS, and All-Intra codecs, together with the potential use of proxy recording, straight influences the general effectivity and effectiveness of the video manufacturing course of, answering the sensible features of “what format ought to I shoot video sony a7iv.”
4. Bit Depth
Bit depth, when thought-about inside the scope of “what format ought to I shoot video Sony a7IV,” refers back to the quantity of colour info saved for every pixel in a video body. It dictates the variety of attainable colour shades and tones that may be represented, straight impacting the smoothness of gradients, the accuracy of colour copy, and the pliability obtainable for colour grading in post-production. The next bit depth, equivalent to 10-bit, permits for considerably extra colour gradations than an 8-bit format, resulting in fewer cases of colour banding and better latitude when adjusting colours throughout enhancing. The Sony a7IV’s skill to report in each 8-bit and 10-bit codecs presents a crucial alternative that aligns with the supposed use of the footage.
The sensible significance of understanding bit depth turns into obvious throughout colour grading. For instance, when capturing landscapes with delicate variations in sky colour, an 8-bit recording might exhibit noticeable steps or bands within the gradient as colours are adjusted. A ten-bit recording, with its elevated colour info, permits for smoother and extra natural-looking changes, leading to a extra polished {and professional} remaining product. Moreover, when capturing in log profiles, that are designed to seize a large dynamic vary for post-production manipulation, 10-bit recording is sort of important to stop posterization and keep the integrity of the dynamic vary changes. Failure to think about bit depth might result in irreversible limitations within the post-production workflow, constraining the flexibility to attain a desired look or right publicity points. The upper bit depth permits higher high quality, higher dynamic vary grading.
In abstract, bit depth is a basic part of the video format choice on the Sony a7IV. Whereas 8-bit recording could also be appropriate for simple tasks with minimal post-processing, 10-bit recording presents superior colour constancy and grading flexibility, significantly for skilled functions and situations requiring intensive colour manipulation. Understanding the connection between bit depth and the supposed post-production workflow is paramount to maximizing the digital camera’s capabilities and reaching optimum outcomes. The challenges related to inadequate bit depth underscore the significance of cautious planning and knowledgeable decision-making when choosing the suitable video format.
5. Colour Profile
The collection of a colour profile is intrinsically linked to figuring out the suitable video format. Inside the framework of the question “what format ought to I shoot video Sony a7IV,” the colour profile acts as a basic parameter influencing the colour house, dynamic vary, and total aesthetic of the recorded footage. The chosen profile straight impacts the information encoded inside the chosen format and influences subsequent post-production capabilities.
-
Customary Colour Profiles (e.g., Customary, Impartial, Vivid)
Customary colour profiles provide a ready-to-use look with reasonable distinction and saturation. These profiles are appropriate for situations the place minimal post-processing is anticipated, and a natural-looking picture is desired straight out of the digital camera. As an example, recording a household occasion the place quick sharing is prioritized over intensive enhancing would profit from a regular profile, guaranteeing the footage is visually pleasing with out requiring additional changes.
-
Logarithmic (Log) Colour Profiles (e.g., S-Log2, S-Log3)
Log profiles, equivalent to S-Log2 and S-Log3, seize a wider dynamic vary by compressing the highlights and shadows. This ends in a flatter, much less saturated picture that requires colour grading in post-production to attain the specified look. Log profiles are important for skilled workflows the place most flexibility in colour correction and grading is required. An instance is capturing a scene with vital distinction between vibrant daylight and deep shadows; a log profile permits for recovering particulars in each areas throughout post-production, making a balanced and visually compelling picture.
-
HLG (Hybrid Log-Gamma)
HLG is a hybrid log-gamma profile designed for quick playback on HDR (Excessive Dynamic Vary) shows. It offers a steadiness between dynamic vary and ease of use, providing a visually pleasing picture with out intensive post-processing whereas nonetheless retaining some grading flexibility. This profile is appropriate for delivering content material on to HDR-compatible gadgets, equivalent to fashionable televisions, with out requiring advanced colour grading workflows. Instance: capturing a scenic vista for quick playback on an HDR tv, offering a vibrant and dynamic viewing expertise.
-
Concerns for Bit Depth and Codec
The collection of a colour profile ought to be thought-about at the side of bit depth and codec decisions. Log profiles, particularly, profit from greater bit depths (10-bit or better) to stop colour banding throughout grading. Equally, the codec ought to be able to preserving the elevated dynamic vary captured by log profiles. Taking pictures S-Log3 in 8-bit might introduce artifacts as a result of restricted colour info, whereas a 10-bit codec offers ample information for clean and correct colour changes. The interaction between colour profile, bit depth, and codec straight influences the ultimate picture high quality and post-production flexibility.
Finally, the colour profile alternative ought to align with the supposed post-production workflow and the specified aesthetic consequence. Customary profiles provide comfort for quick use, whereas log profiles present most flexibility for skilled grading. Understanding the traits of every profile and its implications for subsequent enhancing is essential for making knowledgeable selections and optimizing the video format choice on the Sony a7IV, enabling efficient responses to the preliminary question of “what format ought to I shoot video Sony a7IV.”
6. Storage Capability
Storage capability exerts a direct affect on the collection of video format when using the Sony a7IV. The obtainable cupboard space on the recording media dictates the utmost length of footage that may be captured at a given decision, body charge, codec, and bit depth. Larger-quality video codecs, characterised by bigger file sizes, necessitate better storage capability to accommodate prolonged recording periods. Conversely, extra compressed codecs, whereas economizing on storage, might compromise picture high quality. The consideration of obtainable storage is subsequently a foundational ingredient in figuring out “what format ought to i shoot video sony a7iv.”
As an example, capturing in 4K decision with a excessive bitrate codec, equivalent to XAVC-I, consumes storage at a considerably greater charge than recording in 1080p with XAVC S. A 128GB reminiscence card would possibly suffice for a brief movie challenge in 1080p, whereas the identical card could possibly be quickly stuffed when recording an extended occasion in 4K. Understanding the correlation between video format parameters and storage consumption permits videographers to strategically plan their shoots, guaranteeing ample recording time with out exceeding obtainable house. Failure to adequately assess storage necessities can result in interrupted recording periods, missed alternatives, or the necessity to compromise on desired picture high quality settings.
In conclusion, storage capability acts as a constraint that straight shapes the viable video format choices on the Sony a7IV. By fastidiously evaluating the anticipated recording length and the corresponding storage calls for of various codecs, customers could make knowledgeable selections that steadiness picture high quality with sensible limitations. The efficient administration of storage capability is thus a crucial talent for any videographer in search of to maximise the capabilities of the Sony a7IV and produce high-quality video content material with out encountering storage-related constraints, firmly establishing storage as a key part of “what format ought to i shoot video sony a7iv”.
7. Meant Use
The supposed use of video footage is a main determinant within the choice of an acceptable video format for the Sony a7IV. The final word vacation spot and function of the recorded materials dictate the mandatory technical specs to attain optimum outcomes. Addressing the query of “what format ought to I shoot video Sony a7iv” necessitates a transparent understanding of how the video might be used, distributed, and seen.
-
Skilled Filmmaking and Industrial Initiatives
For skilled filmmaking or business tasks, the place picture high quality and post-production flexibility are paramount, a better decision, bitrate, and bit depth are usually most popular. 4K decision, 10-bit colour depth, and a codec like XAVC-I or XAVC HS are appropriate decisions. These settings present ample information for colour grading, visible results, and delivering a high-quality remaining product for cinema, tv, or internet advertising. The emphasis is on capturing the very best attainable picture constancy to satisfy stringent business requirements.
-
On-line Content material Creation (YouTube, Vimeo)
When creating content material for on-line platforms equivalent to YouTube or Vimeo, a steadiness between picture high quality and file measurement is essential. 1080p or 4K decision with a codec like XAVC S presents a great compromise. Body charges ought to align with the platform’s suggestions (e.g., 24fps, 30fps, or 60fps). Concerns embody web bandwidth limitations and the viewing habits of the audience. File measurement optimization is crucial to make sure clean streaming and accessibility for viewers with various web speeds.
-
Social Media Content material (Instagram, TikTok)
For social media platforms like Instagram or TikTok, the main focus shifts to creating partaking and shareable content material with fast turnaround instances. Decrease resolutions (e.g., 1080p) and shorter recording instances are sometimes ample. Vertical video codecs are ceaselessly employed. Codecs like H.264 are usually suitable and environment friendly for these platforms. The emphasis is on capturing consideration and delivering a message successfully inside the platform’s constraints.
-
Archival Functions and Lengthy-Time period Storage
When preserving video footage for archival functions or long-term storage, the emphasis is on maximizing picture high quality and minimizing future compatibility points. A excessive decision, bitrate, and bit depth are fascinating, together with a codec that’s more likely to stay supported over time. Uncompressed or minimally compressed codecs could also be thought-about. Redundant backup methods are additionally important to stop information loss. The purpose is to make sure that the video footage stays accessible and of top of the range for future generations.
The varied vary of potential makes use of for video footage underscores the significance of aligning the chosen format with the precise necessities of every software. Neglecting the supposed use can result in compromised picture high quality, inefficient workflows, or compatibility points that undermine the effectiveness of the ultimate product. Due to this fact, cautious consideration of the supposed use is paramount when addressing the query of “what format ought to I shoot video Sony a7iv.”
8. Submit-Manufacturing
Submit-production issues considerably affect the collection of a video format. The supposed enhancing workflow, colour grading necessities, and supply specs dictate the mandatory technical traits of the supply footage. The query of “what format ought to I shoot video Sony a7IV” can’t be adequately addressed with out accounting for the influence on post-production processes.
-
Enhancing Software program Compatibility
The chosen video format have to be suitable with the enhancing software program utilized in post-production. Codecs like XAVC S are broadly supported throughout numerous enhancing platforms, whereas extra superior codecs like XAVC HS might require newer variations or particular {hardware} acceleration for optimum efficiency. Incompatibility can result in import errors, playback points, and diminished enhancing effectivity. Instance: A challenge edited in Adobe Premiere Professional would possibly profit from the readily supported XAVC S, whereas DaVinci Resolve might deal with XAVC HS with better ease. Due to this fact, software program functionality straight impacts format alternative.
-
Colour Grading Necessities
Intensive colour grading necessitates a video format with ample bit depth and dynamic vary. 10-bit recordings, significantly these captured in log profiles like S-Log, provide better latitude for colour correction and manipulation with out introducing banding artifacts. 8-bit footage, whereas appropriate for much less demanding tasks, might exhibit limitations when pushed extensively throughout grading. Instance: A cinematic movie requiring stylized colour grading would mandate 10-bit S-Log recording to maximise artistic management. Understanding grading wants dictates recording parameters.
-
Rendering Time and Processing Energy
The complexity of the video format straight impacts rendering instances and processing calls for throughout post-production. Excessive-resolution footage with advanced codecs requires vital processing energy for playback, enhancing, and rendering. Proxy workflows, the place lower-resolution variations of the footage are used for enhancing, can mitigate these calls for. Instance: Enhancing 4K XAVC-I footage on a much less highly effective pc would profit from creating proxy information to enhance responsiveness. Computational assets thus affect the complexity of the captured format.
-
Supply Specs
The ultimate supply format, whether or not for broadcast, streaming, or theatrical launch, imposes particular technical necessities on the supply footage. Broadcast requirements usually dictate specific codecs, resolutions, and body charges. Streaming platforms might have really useful encoding settings for optimum playback. Instance: A video supposed for broadcast tv should adhere to the broadcaster’s particular format pointers, necessitating an identical recording format. Output necessities are subsequently a pivotal consider preliminary format choice.
These sides spotlight the intricate connection between post-production and format choice. Selecting “what format ought to I shoot video Sony a7IV” requires a holistic understanding of the whole manufacturing workflow, from preliminary seize to remaining supply. Prioritizing post-production issues ensures environment friendly enhancing, high-quality outcomes, and adherence to mandatory technical specs.
Steadily Requested Questions
This part addresses frequent inquiries relating to the collection of applicable video codecs when using the Sony a7IV. The data offered goals to make clear the implications of varied settings and help customers in making knowledgeable selections based mostly on their particular wants and aims.
Query 1: Does the Sony a7IV provide RAW video recording internally?
No, the Sony a7IV doesn’t assist inside RAW video recording. Exterior recording through HDMI to a suitable recorder is required for RAW video seize. This limitation ought to be thought-about when evaluating workflow necessities that necessitate RAW format acquisition.
Query 2: What’s the distinction between XAVC S and XAVC HS codecs, and when ought to every be used?
XAVC S employs H.264 compression, offering broad compatibility and reasonable file sizes. XAVC HS makes use of H.265 (HEVC) compression, providing improved compression effectivity and probably smaller file sizes for equal picture high quality. XAVC S is appropriate for general-purpose recording, whereas XAVC HS is advantageous when file measurement optimization is paramount, offered ample processing energy is out there for enhancing.
Query 3: Is 8-bit colour depth ample, or is 10-bit at all times preferable?
10-bit colour depth offers better colour constancy and dynamic vary, providing elevated flexibility for colour grading and decreasing the danger of colour banding. Whereas 10-bit is mostly preferable for skilled functions and tasks requiring intensive post-processing, 8-bit could also be ample for simple recording situations with minimal colour manipulation.
Query 4: How does body charge have an effect on the ultimate video output, and what body charges are really useful for various situations?
Body charge influences the perceived movement and fluidity of video footage. 24fps is usually used for a cinematic aesthetic, 30fps for general-purpose recording, and better body charges (60fps, 120fps) for capturing slow-motion results. The selection of body charge ought to align with the specified visible fashion and the character of the topic being recorded.
Query 5: How does the selection of colour profile influence the post-production workflow?
Customary colour profiles provide a ready-to-use look with minimal post-processing required. Log profiles, equivalent to S-Log, seize a wider dynamic vary, necessitating colour grading in post-production to attain the specified aesthetic. Log profiles present better flexibility for colour correction and inventive grading however require a extra expert post-production workflow.
Query 6: What’s the really useful storage capability for recording 4K video on the Sony a7IV?
The required storage capability is determined by the decision, body charge, codec, and bit depth used. 4K video recording consumes considerably extra storage than 1080p. It’s advisable to make the most of high-capacity SD playing cards (e.g., 128GB or bigger) and estimate recording durations based mostly on the chosen video format parameters to make sure ample cupboard space is out there.
Deciding on the suitable video format for the Sony a7IV entails a multifaceted decision-making course of that considers technical specs, supposed use, and post-production necessities. A radical understanding of those components is essential for maximizing the digital camera’s capabilities and reaching optimum outcomes.
The next part will handle troubleshooting frequent points encountered when working with totally different video codecs on the Sony a7IV.
Taking pictures Video on the Sony a7IV
Optimizing video seize on the Sony a7IV necessitates adherence to particular pointers regarding format choice. The next suggestions are offered to reinforce video high quality and streamline post-production workflows.
Tip 1: Prioritize 10-Bit Recording for Grading Flexibility. If intensive colour grading is anticipated, recording in 10-bit colour depth is strongly really useful. This mitigates banding artifacts and offers a wider vary of adjustable colour info in comparison with 8-bit.
Tip 2: Make the most of S-Log Profiles Strategically. S-Log profiles seize a wider dynamic vary however require meticulous colour correction in post-production. Make use of S-Log settings solely when the post-production workflow contains devoted colour grading experience and applicable software program.
Tip 3: Match Body Charge to Meant Output. When answering “what format ought to I shoot video sony a7iv,” take into account whether or not the ultimate output might be for movie, tv, or on-line platforms. If the goal media is movie at 24 frames a second, or 30 for net video, capturing it within the goal body charge yields a greater consequence.
Tip 4: Steadiness Decision with Storage Capability. Whereas 4K presents enhanced element, it additionally consumes considerably extra cupboard space. Consider the required recording length and storage limitations to find out an applicable steadiness between decision and recording time.
Tip 5: Choose Codecs Based mostly on Enhancing Capabilities. Codecs equivalent to XAVC HS provide environment friendly compression however might require better processing energy for enhancing. Make sure the enhancing system can deal with the chosen codec easily to keep away from efficiency bottlenecks. H.264 is a extra broadly suitable alternative if it is a concern.
Tip 6: Check File Previous to Essential Shoots. Earlier than commencing any essential recording session, carry out take a look at recordings with the chosen format settings to confirm correct publicity, audio ranges, and total picture high quality. This proactive step can forestall unexpected points in the course of the precise shoot.
Tip 7: Take into account Utilizing Exterior Recorders For RAW. As a result of the digital camera shouldn’t be in a position to report in RAW, it’s recommended you employ exterior video recorders if you’ll profit from it, utilizing a suitable recorder will let you profit from RAW capabilities.
Tip 8: Take into account Utilizing Proxy Workflows For Lesser Processors. In case your processor shouldn’t be that highly effective, take into account capturing in proxy to permit for better effectivity with none processing bottlenecks.
Adherence to those suggestions will improve the standard and manageability of video footage captured on the Sony a7IV, in the end enhancing the effectivity and effectiveness of the whole video manufacturing workflow.
The next part will discover troubleshooting frequent points encountered when working with totally different video codecs on the Sony a7IV.
Conclusion
The collection of an applicable video format for the Sony a7IV calls for cautious consideration of a number of interdependent components. Decision, body charge, codec, bit depth, colour profile, storage capability, supposed use, and post-production necessities every contribute to the optimum configuration. A complete understanding of those components, and their interrelationships, facilitates knowledgeable decision-making. The phrase “what format ought to I shoot video sony a7iv” encapsulates this multifaceted decision-making course of, emphasizing the significance of aligning technical specs with particular challenge wants.
Finally, the pursuit of the best video format for the Sony a7IV is a steady strategy of analysis and adaptation. As expertise evolves and inventive calls for shift, videographers should stay vigilant of their evaluation of obtainable choices. Mastery of those rules ensures constantly high-quality outcomes and empowers creators to totally leverage the capabilities of their tools, optimizing the artistic course of to the best extent.
