Sony A7siii with 90mm macro

Hello friends Is there anyone who uses Sony A7siii with nauticam housing Sony 90mm lens I ordered today macro port 105 for Sony 90mm lens part 37126 My question I am using keldan  filter on front of the lens. Will there be space inside the port for the red filter ?

While I don't own that port, in the past I made some measurements of a friend's copy of that lens/port combo. If my measurements were correct, there is only around 1mm of space between the front of the 90mm lens and the port glass. So I don't think there will be enough space for a conventionally-mounted filter. That said, I'm sure you could figure out another way to do it (remove the glass from the filter ring and mount it inside the lens's filter threads, use a 67mm filter on the outside of the port, use a thin gel filter inside the port, etc). 

Thank you lsaac szabo i thank  the lens to close to the glass for super macro lens like cmc /smc I 

Why do you want the red filter on the 90mm macro anyway? Are you shooting in natural light? If you're using LEDs, then at macro distances, their light will utterly dominate the exposure, obviating the need for a red filter.

2 hours ago, Barmaglot said:

Why do you want the red filter on the 90mm macro anyway? Are you shooting in natural light? If you're using LEDs, then at macro distances, their light will utterly dominate the exposure, obviating the need for a red filter.

Absolutely right I have a pair of keldan 12000lm but the background will be a different color If I move a little away from the object

Have you actually tried it? Keep in mind that DoF is very shallow in macro shots, so if the background isn't right next to the subject (in which case it will be well-lit already), it will be way out of focus and completely indiscernible. Let me dig through my library for an example where I have a good amount of separation between a macro subject and its background... ah, there's a good one:

Here we have a pair of ghost pipefish in a crevice. with the back of that crevice maybe 50-80cm behind the fish. This was shot with a Canon 60mm on a Sony A6300, at f/8. You can see how the background is almost completely out of focus - it doesn't really matter what color it is.

Another one, a pikachu on top a hydroid, shot with 90mm macro at f/14:

I was trying to get low enough to put water in the background, but couldn't quite do it. Still, the sandy bottom is utterly unrecognizable.

I should also add that as far as macro shots go, this type of composition is fairly rare. In absolute majority of the shots, the background is right there with your main subject, like this hermit crab (90mm, f/20):

Or, if you're filming something pelagic or sitting on some tall reef feature (say, a whip coral goby), you get pure water in the background, which you can make blue if there's good visibility, or black if there isn't (or you just want a black background), like this trumpetfish (90mm, f/10):

In none of those cases is a red filter of any help. Granted, those were taken with strobes rather than LEDs, but 2x12k is enough power to be competitive with strobes at macro distances, where strobes are used at fairly low power anyway.

5 hours ago, Barmaglot said:

Have you actually tried it? Keep in mind that DoF is very shallow in macro shots, so if the background isn't right next to the subject (in which case it will be well-lit already), it will be way out of focus and completely indiscernible. Let me dig through my library for an example where I have a good amount of separation between a macro subject and its background... ah, there's a good one:

Here we have a pair of ghost pipefish in a crevice. with the back of that crevice maybe 50-80cm behind the fish. This was shot with a Canon 60mm on a Sony A6300, at f/8. You can see how the background is almost completely out of focus - it doesn't really matter what color it is.

Another one, a pikachu on top a hydroid, shot with 90mm macro at f/14:

I was trying to get low enough to put water in the background, but couldn't quite do it. Still, the sandy bottom is utterly unrecognizable.

I should also add that as far as macro shots go, this type of composition is fairly rare. In absolute majority of the shots, the background is right there with your main subject, like this hermit crab (90mm, f/20):

Or, if you're filming something pelagic or sitting on some tall reef feature (say, a whip coral goby), you get pure water in the background, which you can make blue if there's good visibility, or black if there isn't (or you just want a black background), like this trumpetfish (90mm, f/10):

In none of those cases is a red filter of any help. Granted, those were taken with strobes rather than LEDs, but 2x12k is enough power to be competitive with strobes at macro distances, where strobes are used at fairly low power anyway.

Thank you Barmaglot    

A red filter is designed to take excess blue (or blue-green in temperate waters) out of an image by absorbing it, so you are absorbing some of the light from the LEDs. 

If you are using auto WB or manual WB  when you do this the camera will balance the light to daylight and if you have a red filter over your lens it needs to shift the balance further towards blue/cyan than it would if it was using the bare lights.  The background where the contribution of light from your video lights is progressively less will look progressively more Cyan/blue. 

People will shift their lights/strobes colour temperature warmer with filters to achieve about 4500K, but those filters are a very pale yellow/cream colour.  They do this to get a richer blue in the background water as the camera shifts to a cooler white balance and means areas not lit will be a lot bluer.  If you used a red filter it would be an extreme shift and the background would get very blue quite quickly.    There would be no benefit to using a red filter on your lens with lights and I expect the results would look rather odd.

Red Filters are typically used when you are shooting in ambient light with no added lighting.

4 hours ago, ChrisRoss said:

A red filter is designed to take excess blue (or blue-green in temperate waters) out of an image by absorbing it, so you are absorbing some of the light from the LEDs. 

If you are using auto WB or manual WB  when you do this the camera will balance the light to daylight and if you have a red filter over your lens it needs to shift the balance further towards blue/cyan than it would if it was using the bare lights.  The background where the contribution of light from your video lights is progressively less will look progressively more Cyan/blue. 

People will shift their lights/strobes colour temperature warmer with filters to achieve about 4500K, but those filters are a very pale yellow/cream colour.  They do this to get a richer blue in the background water as the camera shifts to a cooler white balance and means areas not lit will be a lot bluer.  If you used a red filter it would be an extreme shift and the background would get very blue quite quickly.    There would be no benefit to using a red filter on your lens with lights and I expect the results would look rather odd.

Red Filters are typically used when you are shooting in ambient light with no added lighting.

Chris - My understanding is that you can also add the filters to your lights to shift them more into blue spectrum (ambient for the depth) so that you can get a well lit scene with lights and still continue to use the red filter.  Let me know if I am missing something with this.

2 hours ago, vaidhy said:

Chris - My understanding is that you can also add the filters to your lights to shift them more into blue spectrum (ambient for the depth) so that you can get a well lit scene with lights and still continue to use the red filter.  Let me know if I am missing something with this.

Yes you can do that, a typical application is for wide angle work, in this case you are trying to match the video lights to the UW colour temperature and the video lights then act as fill light and the red filter acts to colour balance everything from the foreground to the background.  I recall seeing some posts on this topic a while back and it seemed a bit tedious as the red filter and blue filter both need to "match" and be changed at different depths.  The alternative is to colour balance with lights on and the let the background fade to blue which to me looks fine.  Here's a post on the subject: 

View archived post in: Color Filters for Underwater Videography

My lack of understanding about video may be an issue, but I'm going to ask/chime in anyway!

Filters are normally used (whether attached to lens or lights/strobes) to balance the spectrum of light to that encountered underwater. 

When shooting macro, the subject is (normally) lit entirely by the lights. Hence as long as the camera's WB settings match those of the light, no spectrum matching is necessary. i.e. you are not attempting to balance the artificial light with the ambient. 

The background of macro shots is typically not in focus/relevant and creatively, you are normally trying to draw the viewer's attention to the subject? Hence if the spectrum is slightly off, this tends to have limited effect. 

Or have I got it all wrong?

37 minutes ago, adamhanlon said:

My lack of understanding about video may be an issue, but I'm going to ask/chime in anyway!

Filters are normally used (whether attached to lens or lights/strobes) to balance the spectrum of light to that encountered underwater. 

When shooting macro, the subject is (normally) lit entirely by the lights. Hence as long as the camera's WB settings match those of the light, no spectrum matching is necessary. i.e. you are not attempting to balance the artificial light with the ambient. 

The background of macro shots is typically not in focus/relevant and creatively, you are normally trying to draw the viewer's attention to the subject? Hence if the spectrum is slightly off, this tends to have limited effect. 

Or have I got it all wrong?

Agree - not really much help for macro subjects.

11 hours ago, ChrisRoss said:

A red filter is designed to take excess blue (or blue-green in temperate waters) out of an image by absorbing it, so you are absorbing some of the light from the LEDs. 

If you are using auto WB or manual WB  when you do this the camera will balance the light to daylight and if you have a red filter over your lens it needs to shift the balance further towards blue/cyan than it would if it was using the bare lights.  The background where the contribution of light from your video lights is progressively less will look progressively more Cyan/blue. 

People will shift their lights/strobes colour temperature warmer with filters to achieve about 4500K, but those filters are a very pale yellow/cream colour.  They do this to get a richer blue in the background water as the camera shifts to a cooler white balance and means areas not lit will be a lot bluer.  If you used a red filter it would be an extreme shift and the background would get very blue quite quickly.    There would be no benefit to using a red filter on your lens with lights and I expect the results would look rather odd.

Red Filters are typically used when you are shooting in ambient light with no added lighting.

Thank you Chris 

I use a filter for lighting according to what I understood the camera has a hard time to do white balancing without a red filter on the lens what also I sometimes I want to shoot in the same dive portrait fish with same 90mm lens otherwise I would remove filters from the lighting and put 5000 kelvin in the camera my lighting is keldan 12000 flux 5000 kelvin 

4 hours ago, ChrisRoss said:

Yes you can do that, a typical application is for wide angle work, in this case you are trying to match the video lights to the UW colour temperature and the video lights then act as fill light and the red filter acts to colour balance everything from the foreground to the background.  I recall seeing some posts on this topic a while back and it seemed a bit tedious as the red filter and blue filter both need to "match" and be changed at different depths.  The alternative is to colour balance with lights on and the let the background fade to blue which to me looks fine.  Here's a post on the subject: 

View archived post in: Color Filters for Underwater Videography

 

Chris What do you suggest to do a white balance with a gray card and left light  on or set the camera to the Kelvin of the light  in my case it is 5000kelvin

16 hours ago, Eransalah said:

Chris What do you suggest to do a white balance with a gray card and left light  on or set the camera to the Kelvin of the light  in my case it is 5000kelvin

Typically you want to white balance in the light for your main subject.  If you are doing wide angle work with video lights, they are not as powerful as strobes so you would want to WB off a card, either grey or white at at similar distance to subject - this is because there will be a fair amount of ambient light in the mix.  If you are doing macro stills with a good sized subject I would be inclined to Auto WB, that's what I do with strobes - because you are so close with your lights the video light should dominate the scene and be similar to a strobe and typically with strobes I auto WB.

If you are shooting stills, shooting in RAW gives you a lot of headroom to adjust WB in post.  If you are shooting macro video, you don't have the same amount of processing headroom so you want to get it quite close in camera and I would experiment with WB off a card, you can check what the WB chosen is if you shoot a still frame.  If the WB remains consistent you could probably set it to a fixed value, but the required WB will start to vary as you get further from your subject, so you would ned to be aware of that. 

9 hours ago, ChrisRoss said:

Typically you want to white balance in the light for your main subject.  If you are doing wide angle work with video lights, they are not as powerful as strobes so you would want to WB off a card, either grey or white at at similar distance to subject - this is because there will be a fair amount of ambient light in the mix.  If you are doing macro stills with a good sized subject I would be inclined to Auto WB, that's what I do with strobes - because you are so close with your lights the video light should dominate the scene and be similar to a strobe and typically with strobes I auto WB.

If you are shooting stills, shooting in RAW gives you a lot of headroom to adjust WB in post.  If you are shooting macro video, you don't have the same amount of processing headroom so you want to get it quite close in camera and I would experiment with WB off a card, you can check what the WB chosen is if you shoot a still frame.  If the WB remains consistent you could probably set it to a fixed value, but the required WB will start to vary as you get further from your subject, so you would ned to be aware of that. 

Thank you very much