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Night photography tips

Started 6 months ago | Discussions thread
Larry Rexley Senior Member • Posts: 1,238
Re: Astrophotography with EF-M lenses
1

Andy01 wrote:

Larry Rexley wrote:

Andy01 wrote:

Nipar wrote:

Do you think that over ISO 5000 the picture will start being noisy?

Noise is a user tolerance thing so each person may be different. IMO ISO 1600 is about as far as I would go.

That was the world before DxO. If you're willing to shoot RAW and use DxO Deep Prime with DxO PureRaw or PhotoLab 5, you can easily go to ISO 6400 and with careful processing even beyond that to ISO 8000-16000.

https://www.dpreview.com/forums/post/65548513

How well does it work for astro/stars ? Genuine question - I have never used it. Concern is that it may "remove" smaller stars mistaking them for noise ?

DxO handles noise very well, keeping a fair amount of detail even in astrophotos. When I process using Deep prime, I adjust the Deep Prime luminance setting to a point where just a hint of grain still comes through which is also the level which seems to preserve any real detail that's present.

Here's a post with a few astrophotos in an infrared thread I started, they're mostly taken with a Canon M200 which doesn't do quite as well at high ISOs as the M6ii. Some of the shots were taken at 'ISO' speeds of 400 and 800, however all of them were processed with DxO PhotoLab 5 using Deep Prime de-noise, and for all of them I did a lot of curve adjustment and contrast enhancement which would result in noise much more like you would typically see at high ISO's. As a general rule you can probably add about 2-3 EV of ISO due to my bringing out the shadow detail --- so an ISO 800 shot really was pushed to around ISO 3200 - 6400.

https://www.dpreview.com/forums/post/66358186

Where I've been especially impressed with DxO for astro use is its ability to remove low-level deep-shadow chroma noise, which is a bane of astrophotography. They use some algorithm to calculate the original color of sections of an image and are able to reproduce relatively accurate colors in what initially appear to be such color-noisy areas. Sometimes I think an image is going to be unusable due to so much chroma noise--- yet I still get nice results using DxO without all the color noise that was in the original image.

If you're interested in taking pictures like the ones you posted, the methods or techniques vary only slightly, depending on the lens used. The same camera settings

Just one more question: how can I disable the AF and set the focus to infinite with the 11-22 or 32mm?

Don't use "infinity" on any lens, EF-M or otherwise. Even the best MF lens is unlikely to have an infinity mark or hard stop that is accurate enough for stars.

Use Live View, set the screen to maximum magnification (10x ?) and manually focus on a bright star trying to get the star as sharp (small & pinpoint-ish) as possible. Once that is done. make sure you don't touch the focus ring again.

Some lens have a specific leverage but EF-Ms don't (the 32mm has but I don't know what it serves..)

Not sure what you mean by this ? Are you referring to switches built in to the lenses ?

 Larry Rexley's gear list:Larry Rexley's gear list
Canon EOS M6 II Canon EOS M200 Canon EF-M 18-55mm f/3.5-5.6 IS STM Canon EF-M 22mm f/2 STM Canon EF-M 11-22mm f/4-5.6 IS STM +21 more
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