Old lens gives foggy cast

jaab · 01-26-2009, 04:12 AM

Hi Everybody
I have tried to use an old 75to 250mm lens with macro lens on the front ,but the photos aren't clear and have a funny foggy cast any ideas.Photo taken on f8 and 1/50 sec on K10d but I think my settings are wrong somewhere.All my old lenses seem the same .Any ideas.
cheers Jaab

Arjay Bee · 01-26-2009, 07:03 AM

I have some lenses that do that when they have haze on the inner elements. The haze is from oil vaporising from the focus mechanism and condensing on the inner glass. Rectify wlth a service if the lens is worth preserving or try doing it yourself if you want a challenge. Examine the lens by looking through it off camera at an oblique angle when shining light up from the bottom.

I can also cause that effect with any lens when I go outside my airconditioned house etc and the humidity condenses on the front element. Rectify by allowing camera to warm up before use.

jaab · 01-26-2009, 01:26 PM

Thanks Arjay
The lenses work fine on my k1000 film camera,but not on the digital k10d.I have tried all I can think of but with no success,almost seems like the old lenses and the new digital really dont go together at all.The lenses are in almost new condition and have been well looked after.Thanks again

juice · 01-26-2009, 09:48 PM

I had an M42-mount 135mm lens that did seem to have a "cloud" over most of the shots. I sold it off long ago but read just the other day that older lenses may exhibit this behaviour with a bright light source near the frame (eg. the sun). This causes some form of internal flare due to reflections between the camera's sensor and the rear element of the lens.

Apparently new digital lenses have better coatings on the rear element to account for the extra reflectivity of the sensor (vs the film in the old days). Perhaps you are experiencing something like this?

Your grasshopper shot just looks blurry to me though, not the "cloud" that I experienced.

jaab · 01-28-2009, 01:36 AM

Gday
I have tried all my old lenses and they are the same .Looks like the old lenes are compatable as the blurb goes ,they just not complimentary.
cheers and thanks jaab

kevbirder · 01-28-2009, 07:20 AM

It sounds like you are giving up, but actually one of the biggest bonuses of these Pentax cameras is that they do work with older lenses. I have never seen anything like you show here despite using 4 different older lenses all designed for 35mm, one of which is an old screw thread mount.

Are your 'new' lenses OK or don't you actually have any new lenses? I'm just thinking that the fault could be the camera if all pictures are coming out like that. A dirty sensor could cause that effect. My first attempt to clean my sensor resulted in pictures much like yours. It seems I must have smeared some grease around over the sensor. Eventaully I got it clean.

kevbirder · 01-28-2009, 07:22 AM

When I say I haven't seen anything like that before, i mean relating to the actual lenses used.
Obviously I have seen something like that relating to a dirty sensor.

vanchaz2002 · 01-28-2009, 09:03 AM

Does the lens has a filter on? Some low quality filter will cause something like that.

WJW · 01-28-2009, 09:33 AM

Originally Posted by jaab

Hi Everybody
I have tried to use an old 75to 250mm lens with macro lens on the front ,but the photos aren't clear and have a funny foggy cast any ideas.Photo taken on f8 and 1/50 sec on K10d but I think my settings are wrong somewhere.All my old lenses seem the same .Any ideas.

I find some of my old lenses tend to underexpose so you might try changing your exposure from -.3 EV to like +.3 or .6 as a start, unless the background should have been a medium gray. Changing the ISO to 200 should also get a bit more shutter speed and cut down on the slight blur without adding significant noise.

1. Were you using a lens hood?

2. Double check all of the exposed lens filter surfaces for smudges, haze. be sure there was no condensation.

Jeff

Lowell Goudge · 01-28-2009, 10:19 AM

Originally Posted by jaab

Hi Everybody
I have tried to use an old 75to 250mm lens with macro lens on the front ,but the photos aren't clear and have a funny foggy cast any ideas.Photo taken on f8 and 1/50 sec on K10d but I think my settings are wrong somewhere.All my old lenses seem the same .Any ideas.
cheers Jaab

dumb question time, but what focal length did you input, and what focal length did you shoot at.

1/50th is probably too long a time for a macro shot. SR on the K10D is not really (in my opinion) as effective for macro because close focus lenses and close focusing change the effective focal length.

jaab · 01-29-2009, 02:09 AM

GDay
Well there is nothing like a bit of negativity to attract some positivity on this site thanks .Vanchaz thanks the key was in the filter,I took the filter off each lens that I have used and put it on the lens I was using. Macro shots seem pretty good now with this old 28 to 80 sigma,also took 3 photos at different exposure.Thank again I now have renewed vigour towards my camera.
cheers jaab

**Damn Brit** · 01-29-2009, 03:18 AM

Moved to Lens Forum.