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05-04-2012, 11:27 AM   #1
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Zenit 16mm 2.8 Fisheye K mount for Pentax K-5 picture problem. Help please?

Hi this is my first post, and am hoping someone can help me out or point out what is wrong. I just got a used Zenit 16mm 2.8 Fisheye for Pentax K mount from B&H Photo. The lens visually looks fine,and B&H had it listed at 8+ condition. I am using a Pentax K-5. When it got delivered today, I naturally wanted to run outside and take some test pictures to see what kind of pictures it takes. The lens automatically goes in Av mode, I tried letting auto ISO run, and tried manually adjusting ISO as well. I tried a whole range of f-stops from 2.4 to 16, both as JPG and DNG. I should not that the lens does not have the 3 rear filters that it would of come with new, but from reading numerous posts, those filters are not important and shouldn't be used anyway.

So anyway, the problem I am having is that once I imported the pictures to my PC, i realized that they all have SO MUCH grain and look very "blocky". My sensor is clean, and my other lens all take fine pictures. I am hoping the community can take a look and some of these pictures and offer an opinion on whether it is a defective lens or if I am using incorrect settings or whatever the case might be. Thank you.

On my Flickr page for each of these pictures I notated what was obviously wrong to me so look for that. You will need to view the pics in full screen to really see.

ZENIT 16mm 2.8 Fisheye Problem Samples - a set on Flickr

05-04-2012, 01:08 PM   #2
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lets go slowly at this.

can you change modes? or is it always in AV mode?

what is your ISO set to, auto? what are the limits?

Note that with auto ISO set on, the camera in AV mode will try to adjust exposure first by going to maximum ISO before it plays with lens settings.

Also I was not aware the zenitar K mount supported Auto aperture, I have the M42 version.

I would suspect you have more success in manual mode
05-04-2012, 01:30 PM   #3
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Hi cott789,

It seems that you've done at least a few things wrong.

1. Rear filters. One rear filter (usually the UV) *must* be attached to the lens at all times. Otherwise, the lens will not be able to reach infinity. It is possible that your lens already has a small UV filter screwed in.

2. Av mode. In this mode, the "K" lens will ALWAYS remain wide open no matter what aperture you set it to. (Note that this would NOT apply to the M42 version of this lens used with an adapter; M42 lenses are fine in Av mode, K-mount ones without the "A" mode aren't).

3. Make sure to switch to M (Manual) mode. Select aperture on the lens (try f/5.6 first, this seems to be the sharpest aperture on my copy), choose low ISO (100-200). Use the green button to meter: when you push the green button, the camera will stop down the lens and select proper shutter speed.
05-04-2012, 01:40 PM   #4
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Took a look at your pictures, absolutely nothing wrong with the lens in my opinion. The one marked "self evident" is the least evident one. I think you are just being picky about the "grain". I don't know your background with your K-5 or digital/film photos in general, but those are high contrast scenes and the shadows are likely to be a little noisy and appear slightly grainy. Again, if this kind of grain bothers you, you might be allergic to film.
I mentioned about your background with the K-5, because I don't know whether this is your only manual lens. Apparently you aren't using it right. There's a post somewhere around here which will help you improve some aspects of your shooting style with your lens. I will try to sum it up so you don't have to look for it.
Basically, you were using it in Av. That makes the aperture ring unusable, because it will only meter wide open and shoot wide open, regardless of the aperture selected [I'm not going to explain here why]. Looking at your EXIF info, it seems that all of your shots were taken wide open. NO WONDER the image quality suffers. Things like chromatic abberation, softness and maybe that graininess that you are talking about, all of them disappear if you shoot at about f/8 - f/11 in those conditions.
My second point: why use auto ISO? I always like to control my exposure manually, by selecting the lowest ISO that can get me a shot without shake blur, and an aperture closed enough so it will be as sharp as I wish. I only step up from 100 ISO if absolutely necessary.
My third point: I have found out that auto white balance produces weird effects with some lenses, and it's best to either set the white balance manually (in either "daylight" or what balance you prefer), or shoot RAW and correct the cast at home. In some of your shots, the magenta cast is obvious.
Keep taking pictures with that Zenitar, you'll get used to it quickly and it'll produce some amazing pictures for you!

05-04-2012, 01:49 PM   #5
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QuoteOriginally posted by Lowell Goudge Quote
lets go slowly at this.

can you change modes? or is it always in AV mode?

what is your ISO set to, auto? what are the limits?

Note that with auto ISO set on, the camera in AV mode will try to adjust exposure first by going to maximum ISO before it plays with lens settings.

Also I was not aware the zenitar K mount supported Auto aperture, I have the M42 version.

I would suspect you have more success in manual mode

Well, if I choose any of the auto modes (other than green of course) it displays on the screen that it is in Av mode. I can put it in manual and it says manual and I can control everything but the aperture. I have tried composing the same scene in both modes, from ISO 80 up to ISO 800. I have also tried auto ISO. I get the same result every time regardless of those settings (other than the exposure level of course). As far as the mount, it was listed by B&H as PK mount, and it specificaly said in the listing that it was not M42. However, I really wouldn't be able to be certain that it is not M42 since I don't know how to tell. The metal mount has the protruding aperture adjuster, but it also of course has the manual aperture dial on the lens. The print on the lens says MC ZENITAR-K 2,8/16 and the sticker on the case that B&H placed says "Zenit 16/2.8 fisheye F/PENTAX K.
05-04-2012, 01:55 PM   #6
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QuoteOriginally posted by Lowell Goudge Quote
Also I was not aware the zenitar K mount supported Auto aperture, I have the M42 version.
It has an automatic aperture, but lacks automated aperture control (no A-contacts). It has a basic K-mount.

To summarize the points above and to add what I know after several years of ownership:
  • Enable aperture ring (menu setting)
  • Shoot in M mode using "green button" (stop-down) metering. Alternatively, use a hand-held meter with a gray card.
  • Despite the extreme wide angle, focus is actually fairly critical with this lens and very hard to attain using the stock focus screen. A split image or microprism focus aid helps immensely.
  • Best sharpness is found from f/5.6 to f/16
  • There must always be a filter attached at the rear of the lens. All Zenitar fisheyes shipped with four filters...one (clear) attached and three others (red, green, and yellow) in a small case. If yours is missing its clear filter, send it back.
  • Don't loose the lens cap
Enjoy!


Steve
05-04-2012, 01:56 PM   #7
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QuoteOriginally posted by aoleg Quote
Hi cott789,

It seems that you've done at least a few things wrong.

1. Rear filters. One rear filter (usually the UV) *must* be attached to the lens at all times. Otherwise, the lens will not be able to reach infinity. It is possible that your lens already has a small UV filter screwed in.

2. Av mode. In this mode, the "K" lens will ALWAYS remain wide open no matter what aperture you set it to. (Note that this would NOT apply to the M42 version of this lens used with an adapter; M42 lenses are fine in Av mode, K-mount ones without the "A" mode aren't).

3. Make sure to switch to M (Manual) mode. Select aperture on the lens (try f/5.6 first, this seems to be the sharpest aperture on my copy), choose low ISO (100-200). Use the green button to meter: when you push the green button, the camera will stop down the lens and select proper shutter speed.

As I said, the used item did not come with the rear filters. I went to Zenit's website and sent an email using the link they provided for the purpose of trying to order them, but the email was returned as not deliverable. I am aware of the fact that the aperture will remain wide open in Av mode regardless of settings. That is why I tried I switched to M mode. I will try keeping it at 5.6 and low ISO and use the green button to meter. Thanks.
05-04-2012, 02:01 PM   #8
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QuoteOriginally posted by cott789 Quote
Well, if I choose any of the auto modes (other than green of course) it displays on the screen that it is in Av mode. I can put it in manual and it says manual and I can control everything but the aperture. I have tried composing the same scene in both modes, from ISO 80 up to ISO 800. I have also tried auto ISO. I get the same result every time regardless of those settings (other than the exposure level of course). As far as the mount, it was listed by B&H as PK mount, and it specificaly said in the listing that it was not M42. However, I really wouldn't be able to be certain that it is not M42 since I don't know how to tell. The metal mount has the protruding aperture adjuster, but it also of course has the manual aperture dial on the lens. The print on the lens says MC ZENITAR-K 2,8/16 and the sticker on the case that B&H placed says "Zenit 16/2.8 fisheye F/PENTAX K.
  • To control aperture, use the aperture ring on the lens barrel
  • PK is K-mount (like your camera)
  • M42 is Pentax/Praktica screwmount (used on many film cameras up until fairly recently)
Your lens on the K5 is used the same as any other standard K-mount optic. See my comment above or the sticky of this site regarding metering with legacy lenses.


Steve

05-04-2012, 02:03 PM   #9
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QuoteOriginally posted by cott789 Quote
As I said, the used item did not come with the rear filters.
It should at least have come with the clear one. If it is gone, the lens cannot be used and you should request a return from B&H.


Steve
05-04-2012, 02:08 PM   #10
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QuoteOriginally posted by kcobain1992 Quote
Took a look at your pictures, absolutely nothing wrong with the lens in my opinion. The one marked "self evident" is the least evident one. I think you are just being picky about the "grain". I don't know your background with your K-5 or digital/film photos in general, but those are high contrast scenes and the shadows are likely to be a little noisy and appear slightly grainy. Again, if this kind of grain bothers you, you might be allergic to film.
I mentioned about your background with the K-5, because I don't know whether this is your only manual lens. Apparently you aren't using it right. There's a post somewhere around here which will help you improve some aspects of your shooting style with your lens. I will try to sum it up so you don't have to look for it.
Basically, you were using it in Av. That makes the aperture ring unusable, because it will only meter wide open and shoot wide open, regardless of the aperture selected [I'm not going to explain here why]. Looking at your EXIF info, it seems that all of your shots were taken wide open. NO WONDER the image quality suffers. Things like chromatic abberation, softness and maybe that graininess that you are talking about, all of them disappear if you shoot at about f/8 - f/11 in those conditions.
My second point: why use auto ISO? I always like to control my exposure manually, by selecting the lowest ISO that can get me a shot without shake blur, and an aperture closed enough so it will be as sharp as I wish. I only step up from 100 ISO if absolutely necessary.
My third point: I have found out that auto white balance produces weird effects with some lenses, and it's best to either set the white balance manually (in either "daylight" or what balance you prefer), or shoot RAW and correct the cast at home. In some of your shots, the magenta cast is obvious.
Keep taking pictures with that Zenitar, you'll get used to it quickly and it'll produce some amazing pictures for you!

This is not my only manual lens, I actually have quite a few... I do realize why shooting in Av is an error, you should know that those pictures, the exif data might say they were all shot 2.4, (which they were when in Av mode), but I did know not to use 2.4, I just didn't realize that it was going to shoot that way regardless, thats why after finding that out, i went outside and tried some more pics in M mode stopping down the aperture more. The results were the same however. As far as auto ISO, I only did it to try to troubleshoot possible user error, normally I always force ISO between 80-200. As far as the WB, that I did not try, left it in auto, I am going to go try manual WB in a moment. As far as RAW, I always shoot in RAW, the pics in Flickr were JPG because I converted them for the purpose of uploading. I really do like the framing that this lens allows! Just gotta figure out what these other issues are about. Also another response in this thread stated that the rear filters are in fact needed and that if I didn't get them, I should return the lens. I did not get them, as I stated in the OP. I tried going to Zenit's website and sending them an email on their provided link to see if I can purchase the filters directly from them, however the email was returned as "un-deliverable". Any idea where else I could obtain those filters? I tried ebay and nothing.....
05-04-2012, 02:28 PM   #11
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QuoteOriginally posted by cott789 Quote
I tried going to Zenit's website and sending them an email on their provided link to see if I can purchase the filters directly from them, however the email was returned as "un-deliverable". Any idea where else I could obtain those filters? I tried ebay and nothing.....
The filters are hard to come by and it is not unusual to find them missing, though the clear one is usually where it is supposed to be. Just in case you are wondering, zenitcamera.com is not the KMZ Web site. Try this one:

http://www.zenit-foto.ru/

It is in Russian, but Google translate may be of help. As for sales/marketing...

marketing@zenit-kmz.ru, reklama@zenit-kmz.ru


Steve
05-04-2012, 02:33 PM   #12
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Ok

Now we know exactly. You should be in manual mode, set amputee with the aperture ring, meter with green button, and shoot
05-04-2012, 02:59 PM   #13
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QuoteOriginally posted by stevebrot Quote
The filters are hard to come by and it is not unusual to find them missing, though the clear one is usually where it is supposed to be. Just in case you are wondering, zenitcamera.com is not the KMZ Web site. Try this one:

??? ????????????? ????? ??. ?.?. ???????

It is in Russian, but Google translate may be of help. As for sales/marketing...

marketing@zenit-kmz.ru, reklama@zenit-kmz.ru


Steve
OK, I will try that, thanks! I went previously to Zenit Cameras and sent them email at support@zenit-camera.com via their support link Zenit Cameras (the one that is undeliverable)

I will try your link now.
05-04-2012, 03:05 PM   #14
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QuoteOriginally posted by Lowell Goudge Quote
Ok

Now we know exactly. You should be in manual mode, set amputee with the aperture ring, meter with green button, and shoot
I know that I have to shoot in manual mode. As I said in a few posts, I did that and the results were the same.
05-04-2012, 03:17 PM   #15
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Yes, but you see, I still strongly believe that all your pictures were taken wide open, and here's why: there isn't a single exposure taken at less than 1/640. In fact, you have 3 exposures at 1/2000th of a second, 3 at 1/4000, 2 at 1/6400, one at 1/1600 and one at 1/8000. If I were you, I'd close the aperture all the way, and then take a picture so I can actually if the aperture is closing or not.
By the way, M42 mean screw mount, you screw the lens to keep it fixed. Pentax K is a bayonet mount - you only twist it about 60 degrees and it is locked.
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