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2 Days Ago   #1
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Coastar 28mm f/2.8 No. 440222

Took this with my new (to me) Coastar Lens. It's my second "bargain" 28mm that's absolute junk (not as bad as my last one, but still, there's no clear image to be had with these lenses on a DSLR - this lens is circa 1970's.

Anyone got advice on getting these lenses to take a decent image w/out all the haze, and afterglow (Tried several different f stops, speeds, lighting, etc.. ).

My other 28mm that sucks even worse is a GLC Series Automatic 28mm f/2.8 No. 8781659 (circa 1990's).


My search for a good 'enough' 28mm for my K10D continues.

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2 Days Ago - 1 Like   #2
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Try a circular polarizer.
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Stop down the lens to f8 and see what things look like. Also make sure the lens is actually stopping down properly. Ensure you've got proper focus as well; you may be slightly front-focused in the shot you've shared, but it's hard to know for sure.
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What aperture are you shooting at for the above shot, may I ask?

I've owned and shot with some pretty cheap and nasty lenses (including a number of 28mm models), but so long as the optical elements were in good condition and there was no haze, fungus etc., I've never had one that performed quite so badly as this. Wide open they may not be that useful (depending on personal tastes and expectations), but stopped down to f/5.6 - f/8 they're usually at least OK.

Assuming the glass is in good condition, it could be that you're having a problem with accurate focusing. With no live view on the K10D, it can be tricky to ensure perfect focus. The leaves at the very front of the above shot look like they're reasonably sharp, and I'm wondering if the actual focus point is even a little further in front? Try shooting a brick wall at an angle of, say, 45 degrees to see if the part you focused on, or any region in front or behind, is sharp. Also, try shooting away from the sun to avoid veiling flare. Use a suitable hood or your hand to block out bright light sources...

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For old glass with no/poor coatings, I found using the deepest hood I could find that did not vignette would help with the haze.

As to sharpness, while cheap 28mms are common as sparrows, sharp ones can be hard to find (by today's standards of sharpness).
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There may still be good choices out there that are inexpensive. The Pentax-M 28mm f3.5 is a good example. The K version is even better but borderline not inexpensive.
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Lenses from Tokina, Cosina, or similarly "good third parties" would be a good option in general. They should be quite inexpensive.

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Old photo magazine tests of various 28mm's here - Photographic equipment Photo Gallery by Steve Flynn at pbase.com


Pentax M28 f2.8 comes out best, Tokina next best.
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QuoteOriginally posted by steephill Quote
Old photo magazine tests of various 28mm's here - Photographic equipment Photo Gallery by Steve Flynn at pbase.com


Pentax M28 f2.8 comes out best, Tokina next best.
I have a couple of the Tokina RMC 28mm f/2.8 lenses, each slightly different styling, and both are pretty decent. They crop up frequently for very little money...
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QuoteOriginally posted by steephill Quote
Old photo magazine tests of various 28mm's here - Photographic equipment Photo Gallery by Steve Flynn at pbase.com


Pentax M28 f2.8 comes out best, Tokina next best.
And that's the early M 28 f2.8, with the chrome nose, instead of the mk2 that lacks the chrome ring at the front. Mk2 is supposed to be the better performer of the pair.
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