Noob to the site, but not a noob to photography

[St0rmChaser]

I'm Robert, a storm chaser / astrophotography buff from the high desert of central Oregon.

I have a question and can't figure out where to ask it. If this is not the appropriate place, perhaps one of the advanced users can steer me that way?

I've recently begun playing around with a super dark (10-stop) no-gradient filter for the purpose of capturing the eerie effects of motion during daylight as viewed through a long exposure of 20 seconds up to several minutes. I purchased one to fit onto my Canon 6D2, a "P series" from bhphotovideo. It seems each photo I take with the 10-stop filter produces an image with an apparent reflection of light on the lens glass. I don't know how this is possible, but more importantly, I have no clue how to remedy it.

If anyone does, your advice is appreciated. Thanks in advance.

 

[Jeff15]

Hello and welcome.....

 

[Tropicalmemories]

Hi and welcome.

I think some internal reflections will be inevitable, and they will show due to the low light and long exposure.

A good quality multi coated lens to reduce reflections off the lens surface, plus a filter with coatings on both sides, plus a lens hood or external shade that covers the filter (perhaps one designed for video?) Should help.

 

[weepete]

There's a few things that could be going on. If you're using a filter holder make sure that no light is entering from the sides, if it is you may need to make sime kind of shroud to stop it. Also use the slot in the filter holder that's closer to the camera first. It might be that you're getting reflections through the viewfinder, so try covering it (you camera should have come with a rubber viewfinder cover for long exposure shots). What focal length are you using?

 

[Soocom1]

I would summon up lens flare. Light leaking theough the back of the filter will blow out your image every time.

As stated above, try to stop all light leaks. Think of a garden hose. If it has holes in it the water doesnt flow right. If there is any light leakage, itll blow your image every time.

There are lens bellows that will act like a lens shade.



I hate auto correct on phones.

 

[St0rmChaser]

I would summon up lens flare. Light leaking theough the back of the filter will blow out your image every time.

As stated above, try to stop all light leaks. Think of a garden hose. If it has holes in it the water doesnt flow right. If there is any light leakage, itll blow your image every time.

There are lens bellows that will act like a lens shade.



I hate auto correct on phones.

Thanks for all the suggestions.

I had considered light leaking in fron the sides as the culprit. I'll rig something to work with that. I think the filter is already on the closest of the 3 slots, but I'll verify. Focal length was probably in the middle of my Tamron 24-70mm lens, so it was most likely around 35-50mm.

Thanks again for all the ideas and help.

 

[Derrel]

Gaffer tape the light leak area

 

[weepete]

Thanks for all the suggestions.

I had considered light leaking in fron the sides as the culprit. I'll rig something to work with that. I think the filter is already on the closest of the 3 slots, but I'll verify. Focal length was probably in the middle of my Tamron 24-70mm lens, so it was most likely around 35-50mm.

Thanks again for all the ideas and help.

Yeah, sometimes s hand over the side can be enough. Lee do a universal hood for their 100mm system, but the P filters are smaller so it'd require some creativity to use and is likely expensive.

Probably better rigging up something yourself.

Gaffer tape the light leak area

Will work, though getting the adhesive residue off the filters can be a pain. Electrical tape can also lead to smearing. I'd suggest a fabric and some velcro, though at a push you can cut a hole in a black sock.

 

[St0rmChaser]

Thanks for all the suggestions.

I had considered light leaking in fron the sides as the culprit. I'll rig something to work with that. I think the filter is already on the closest of the 3 slots, but I'll verify. Focal length was probably in the middle of my Tamron 24-70mm lens, so it was most likely around 35-50mm.

Thanks again for all the ideas and help.

Yeah, sometimes s hand over the side can be enough. Lee do a universal hood for their 100mm system, but the P filters are smaller so it'd require some creativity to use and is likely expensive.

Probably better rigging up something yourself.

Gaffer tape the light leak area

Will work, though getting the adhesive residue off the filters can be a pain. Electrical tape can also lead to smearing. I'd suggest a fabric and some velcro, though at a push you can cut a hole in a black sock.

I'm looking for a medium sized black towel to wrap around the lens and filter apparatus. That sounds like the cleanest solution.