Lens recommendations for indoor sports

[Macroramphosis]

No, Ive never cleaned them, Walter. I'll see if I can find some of the cleaner you recommend and give it a go. Thanks for the tip...

 

[Holoholo55]

No, Ive never cleaned them, Walter. I'll see if I can find some of the cleaner you recommend and give it a go. Thanks for the tip...

I like DeOXIT because it does a great job and helps to preserve the contacts. Dunno if you can get it, but you can ask at your local electronics parts store. I've been using it for years. It's great on audio equipment too, which is when I first learned about it. https://caig.com

I even use it on AC plugs to ease the connection and make sure the contacts are clean.

It may be available from Amazon in France. Ah, Caig says it's available here. It's not cheap, but a little goes a long way.
https://www.cotelec.fr/boutique/produits-d-entretien-caig/

If you can't find DeOXIT, you can try a cotton swab lightly dampened with another contact cleaner. Don't use a pencil eraser as some do. Leaves crumbs in your camera and abrades the gold plating on the contacts.

 

[Macroramphosis]

Wow - thank you Walter! That's brilliant. Never heard of the stuff but will ask the finance committee if we can indent for some. Thanks for the additional info too....much, much obliged.

 

[JanW]

And one comment about different AF systems. Four thirds cameras were were still traditional SLR:s and used separate AF modules as all SLR:s had done since 35mm film era. So if four thirds lenses were ever optimized for anything, it was for this separate AF module which required two mirrors to get light in the first place, not for the in-sensor hybrid AF cells which only came to MFT bodies in OM-D E1 in 2013.

I have also never seen a writer who could explain how it is even possible to create a lens which does not support CDAF because this AF system simply analyzes the very image that camera is reading from the sensor.

The only thing limiting CDAF speed and accuracy is the amount of processing power available for AF algorithms and of course those serial commands which are used to move focus elements inside the lens around but PDAF is equally limited by this too ... unless camera manufacturer happens to have a set of proprietary commands which only their bodies can use when it's communicating with their lenses...

First of all my apologies to Macroramphosis for using his thread about lenses for indoor tennis to discuss AF systems.
It's just that there is misinformation in this thread that I would like to address. This will be my last post on the subject.

@BDR-529 seems to look at this from the current state of technology and seems to have no knowledge about the development of live view systems in DSLR cameras that took place approx 10 years ago.
Since this feature was introduced the lens design had to be changed in order to let these lenses work fast (for it's time that is..) and reliable with live view (=cdaf) systems.
This is when Olympus stopped using SWD motors in their lenses. Edit: and other motors that were not compatible (thanks PakkyT).
I believe that Canon did something similar by using MSC motors instead of Ultrasonic motors. But I'm not a Canon user so I'm happy to stand corrected.
I did some quick Google search and found a letter from Olympus USA explainig lens compatibility to their customers.
https://www.google.com/url?sa=t&sou...FjAAegQIARAB&usg=AOvVaw0MlhTQJFjD2mYuuB4TeN6O
It's a link to the search results, I couldn't paste the direct link.
If it doesn't work, Google 'Olympus high speed imager AF' and it's the first result.

I hope this clarifies things and that the information can help users decide if they want to use certain 4/3 lenses on their current camera or not.

Jan

 

[PakkyT]

This is when Olympus stopped using SWD motors in their lenses.

Olympus didn't go big into SWD motors in the first place. I am only aware of 3 lenses that had SWD motors out of the two dozen (including redesigns) or so lenses they made for the 4/3rds system.

 

[BDR-529]

This is when Olympus stopped using SWD motors in their lenses. Edit: and other motors that were not compatible (thanks PakkyT).
I believe that Canon did something similar by using MSC motors instead of Ultrasonic motors. But I'm not a Canon user so I'm happy to stand corrected.

I hope this clarifies things and that the information can help users decide if they want to use certain 4/3 lenses on their current camera or not.

It's totally irrelevant what type of motor is used to move focus group inside the lens as far as differences betweren CDAF and PDAF are concerned.

Whatever the focus technology is, it is located inside the camera body and just sends orders to lens via serial communication. Lens has no knowledge whatsoever about what kind of AF system is communicating with it. Orders are executed all the same regardles of what method is used to determine in what direction and how far the focus group should move and when it should stop.

The only functional difference is in how PDAF and CDAF need to move the focus group. If we oversimplify a *lot* it goes like this

- PDAF can determine in what direction and how far the focus group should move but after this command is executed, PDAF can't be sure whether the focus is absolutely spot on. (This is why modern ILC:s use hybrid AF where final adjustment is done with CDAF after PDAF first adjusted the focus as good as possible). Essentially PDAF can just order the lens to move focus 157 steps in that direction and when lens acknowledges that operation is completed, AF allows shutter to operate.

- CDAF doesn't initially know in what direction focus group should move so it first has to order it slightly in one direction to see if things improve or get worse. CDAF (without DFD) still doesn't know how far it should go so it has to move focus in small increments untill it overshoots and realizes that it needs to get one step back.

CDAF will always know when it has reached the best possible focus for this very lens at this aperture and focal length no matter what the lens is because it's analyzing the very image that sensor is recording. There is no such thing as lens that is "not CDAF compatible". This is nonsense. CDAF works exactly like manual focus where you just use naked eye to determine when the image is as sharp as possible. You alwys need to overshoot focus to know where the sweet spot is and then turn back.

The only thing that lens manufactures can optimize for CDAF (other than use of DFD) is to create motor and lens-body communication which can execute extremely fast huge amounts of these tiny movements and also change direction of movement with extreme accuracy. This is not trivial since there's always some slack if you first move in one direction and then try to yank it back just a tiny bit.

 

[Mike Wingate]

Motors in lenses, whatever next.....auto focus?

 

[Bytesmiths]

Motors in lenses, whatever next.....auto focus?

I know!

It's all a bit much for me. Think I'll stick to my OM Zuikos.

 

[BDR-529]

Am I looking in vain for a m4/3 solution, and should I perhaps be buying something FF (or ASP-C) for what I want to do? If I have to buy something specific, I'd rather buy something that is known to work rather than something that might do the job. Anyone who mentions a Sony A9ii will get a raspberry in their ear

As always, all suggestions are much appreciated.

A couple of weeks ago I finally purchased Topaz Denoise AI to check - among other things - whether I could shoot soccer with my inexpensive panny 45-200mm f/4-5.6 during dark winter months. Well, the answer for most outdoor fields is no because they just don't have enough light.

Even when I pushed ISO to 25600, used 100mm focal length to keep aperture at f/4 and waited untill one of the players walked on a particularly bright spot, shutter speed was still only 1/250s. So no way I could shoot the actual match with this lens but just look what Topaz did to this ISO 25600 image.

If you have a lens that's almost fast enough at whatever ISO you have previously used, Topaz might be a $79 solution which enables you to push it a couple of full stops faster.

ISO 25600 Camera jpg (lossless crop made with Ifranview)

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Same ISO 25600 RW2 denoised with Topaz and cropped to jpg with Darktable (I had to fix white balance and exposure because Topaz alters them)

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[BDR-529]

I forgot to add the full size ISO 25600 RAW image after Topaz Denoise (white balance & exposure correction with Darktable) to give an idea about how tight the previous crop was.

If only ISO 25600 would have been enough to keep the shutter speed below 1/500s up to f/5.6 even these images would have been perfectly usable but no. I might have more luck with indoor venues because they have usually way brighter lights.

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And the previous crop of the original RAW file before any denoise. Even in-camera jpg does a good job at patching up all this noise into sort of van Gogh painting (without the price tag, unfortunately) but Topaz algorithms actually remove it. After few tests I have noticed that Topaz does spectacular job only when the image is otherwise absolutely flawless. Focus must be spot on, exposure as well and there can't be any blur due to camera movement.

So, as long as the only defect in a perfect picture is digital noise, I have not found any hard limit for max ISO Topaz can't fix (of course the result gets softer and loses details & contrast the higher you go) but this SW is definitely an alternative for moving from m4/3 to FF just because of low light IQ.

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[rfortson]

Would the M.Zuiko 75/1.8 or the 45/1.8 work? Collects more light, though not sure of the AF speed of the 75. But like others have said, anticipation and a little luck can get some good shots.