Dust On P25 Jewelry Shots

[juiceboy99]

I am shooting Jewelry shots with a P25 Hasselblad 503CW
and 120mm Macro lens at mostly F 22.

I cleaned the sensor and blew it clean,
but i am gettting many dust spots all over the image !

Is this because i am shooting at F 22 ?
or is dust inevitable when shooting things on white ?

Is there any other precautions i can take to avoid Dust ?

Thanks !

[michaelnotar]

yes f22 is a no no. i usually stay 1 stop away from the smallest f stop for diffraction reasons. usually for macro, DOF isnt much, so i dont try to reinvent the wheel and accept it shooting at f11 to 16 max. even the best cleaning with show at f 22. with my DSLR i usually shoot f5.6-8 to check cleanliness and then f22 to see all the dust.

and jewelry needs lots of retouching, i spent 2-3 hours per shot on a project i shot with my P25 and that was mainly for product dust.

[michaelnotar]

wow i would also clean your back that looks pretty dirty.

[Dale Allyn]

I shoot a P25+ with the 120mm macro at small aperture regularly (on similar subject matter), and I rarely get dust that causes a lot of work. I try to shoot at f/14 to f/20 if possible, but I'm not afraid of f/22 if it is required. Sure, diffraction creeps in, but there will always be a trade-off with macro. One can focus-stack, if that's acceptable to you, or use T-S tools to take advantage of the scheimpflug principle when diffraction is too great to deal with.

Another alternative, depending on absolute resolution requirements, is to back away a little and shoot at f/14 to f/16 and then crop a little.

In any case, your sensor looks very dirty in your sample. I hope that you can resolve that so that it doesn't dictate your camera settings and composition practices.

[Dustbak]

Indeed I would stay away from it and use focus stacking at f16 before going to f22 if I would have to use a system without tilt.

This is way too much dirt after having it cleaned! A good cleaning should make your back clean enough to shoot at f22. Try cleaning it again with something like a pac-pad and fluid if you didn't do so already. This should get your problem down to at most some spots. If this doesn't change it might be the spots are not on top of the IR filter.

[ThierryH]

Your IR protection filter is definitively dirty, probably not with dust, but with stains (saliva or others). A few suggestions:

- make first sure that these spots are on the top of your IR filter, not below or on the surface of the CCD itself.

- cleaning of stains should be done in 2 steps: first by using an "Antistatic Cleaning Solution" on a clean "Micro Fiber Cloth". Always wipe in one and the same direction, e.g. from left to right, gently and a few times, by changing the position of the cloth. Then use a new cleaning cloth with an "ethanol 96% - H2O 4% demineralized." solution to assure a homogenous drying. This should get rid of any type of stains if they are effectively on the top of your IR filter.

- if it happens that the stains are under the IR filter, then you have no other choice but to send your back to your dealer/manufacturer.

Best regards,
Thierry

[Ken]

1. Have you been getting that much "dust" since you've had the back?

2. Is the "dust" pattern always the same?

3. What solutions, materials, method or product do you use for cleaning?

[BobDavid]

I shoot a P25+ with the 120mm macro at small aperture regularly (on similar subject matter), and I rarely get dust that causes a lot of work. I try to shoot at f/14 to f/20 if possible, but I'm not afraid of f/22 if it is required. Sure, diffraction creeps in, but there will always be a trade-off with macro. One can focus-stack, if that's acceptable to you, or use T-S tools to take advantage of the scheimpflug principle when diffraction is too great to deal with.

Another alternative, depending on absolute resolution requirements, is to back away a little and shoot at f/14 to f/16 and then crop a little.

In any case, your sensor looks very dirty in your sample. I hope that you can resolve that so that it doesn't dictate your camera settings and composition practices.

The best thing to do is to back away a little bit. You'll get better depth-of-field and you won't have to shoot at f/22.

[juiceboy99]

The best thing to do is to back away a little bit. You'll get better depth-of-field and you won't have to shoot at f/22.

Ok,  I just thought that filling the entire frame gave the best quality.
That's why i didn't back off...

[juiceboy99]

Ok,  I just thought that filling the entire frame gave the best quality.
That's why i didn't back off...

Has anyone used Merging Software for Merging Different Focus Points together ?

[Tgrain]

Did you use a "rocket" or canned air to blow of your sensor?  I have had spots like that when I used canned air.  With the rocket...no problem

[Dustbak]

Ok,  I just thought that filling the entire frame gave the best quality.
That's why i didn't back off...

You will loose resolution of course but gain DoF and in most cases some quality as well because most lenses perform lesser at distances so close.

[juiceboy99]

You will loose resolution of course but gain DoF and in most cases some quality as well because most lenses perform lesser at distances so close.

Yeah,  I used a Rocket Blower,  but that didn't seem to work....
I guess i should give a wipe down with the cleaner solution.

[yaya]

Yeah,  I used a Rocket Blower,  but that didn't seem to work....
I guess i should give a wipe down with the cleaner solution.

If there are spots/ marks on the outside of the IR filter you should be able to see them with a loupe, otherwise they are on the inside of the filter.

Any dirt on the sensor itself will appear IN focus rather than blurred.

Hope this helps