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Weird shadow at the top of pictures

Started Sep 2, 2018 | Discussions
Matei111 New Member • Posts: 2
Weird shadow at the top of pictures

Hey guys,

I have a Canon T6 (1300D) and a tair-3 lens mounted with an m42 to eos adapter. I recently noticed a black shadow/gradient band at the top of the picture which is most noticeable when framing the sky at the top.

You can see it in this picture.

It is even more noticeable when shooting in portrait.

And, if not shooting the sky the band/gradient is not visible

I suspected this to be a sensor issue so I switched the lens with the ef-s 10-18 and I have nothing like this:

Can you please help me with some suggestion about what can cause this issue?

Thank you in advance.

Matei

Canon EOS Rebel T6 (EOS 1300D)
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crashpc Veteran Member • Posts: 7,240
Re: Weird shadow at the top of pictures

Either camera shutter issue, lens aperture issue, or obstacle in camera vision (filters, hoods, decentered lens, etc.).

 crashpc's gear list:crashpc's gear list
Canon EOS M10 Canon EF-M 15-45mm F3.5-6.3 IS STM
brightcolours Forum Pro • Posts: 15,885
Re: Weird shadow at the top of pictures
1

What is a tiar 3 lens? It should not be the mirror, since then you would have a shadow on the bottom. What is the difference in exposure time, between images that show the issue and images that don't?

OP Matei111 New Member • Posts: 2
Re: Weird shadow at the top of pictures

Tair-3 is a vintage soviet lens. It was meant for a 35mm Zenit camera. It has 300mm (480mm on my crop sensor) with f4.5.

I also took more pictures in the last days. I don't think it is a sensor or mirror issue because with othere lenses I have no problem (I tried the EF-S 10-18 and the EF-S 18-55).

The strange thing is that it happens especially  when shooting against the sky.

Those two picture were taken with same apperture, same ISO, the only difference is in the shutter speed. You can notice how the picture that frames the sky at the top appears to have the black gradient.

However, I noticed that this issue only happen at f4.5. When I switch it to f8 there is almost nothing.

Photo taken at f4.5

Photo taken at f8

I have no ideea what this might be, but it very weird.

brightcolours Forum Pro • Posts: 15,885
It can be the camera

Matei111 wrote:

Tair-3 is a vintage soviet lens. It was meant for a 35mm Zenit camera. It has 300mm (480mm on my crop sensor) with f4.5.

I also took more pictures in the last days. I don't think it is a sensor or mirror issue because with othere lenses I have no problem (I tried the EF-S 10-18 and the EF-S 18-55).

The strange thing is that it happens especially when shooting against the sky.

Those two picture were taken with same apperture, same ISO, the only difference is in the shutter speed. You can notice how the picture that frames the sky at the top appears to have the black gradient.

However, I noticed that this issue only happen at f4.5. When I switch it to f8 there is almost nothing.

Photo taken at f4.5

Photo taken at f8

I have no ideea what this might be, but it very weird.

What I notice is the exposure time difference:

1/4000th sec big issue, 1/2500th sec big but lesser issue, longer exposure times no issue.

Try with a normal EF lens with 1/4000th or 1/2500th sec and see if the issue is there or not?

ThrillaMozilla Veteran Member • Posts: 7,681
Re: Weird shadow at the top of pictures
2

Matei111 wrote:

However, I noticed that this issue only happen at f4.5. When I switch it to f8 there is almost nothing.

Brightcolors is onto something.

You have two choices. Shutter or aperture. With the lens mounted on the camera, look backwards through the lens with the aperture open. If there is any obstruction, you should see it.

If there isn't an obstruction, the problem is probably the shutter. With another lens, take pictures of a uniform subject like a wall or piece of paper -- one at 1/4000 and another at say, 1/1000 or longer. Preferably 1/200 or 1/250 or longer.

People need to learn to look backwards through the lens. You can diagnose all kinds of problems by doing that.

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Canon EOS Rebel SL1 Canon EOS M6 II Canon EF 400mm f/5.6L USM
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