Sony 24-70 f2.8 GM Infinity Focus

[Aquilla]

Been trying to use the above lens for Astrophotography, don’t know how to set it for infinity as it has no scale. When I zoom in on my star photos the stars look like Polo Mints rather than points of light. Any suggestions?

[LiveShots]

Did you try setting to manual focus and then focus on something larger, like the moon.

[Username]

`   

  

No mention in the OP of the current approach 

to focusing for astro.  

   

My suggested solution is to NOT use any fast 

zoom lens when a top quality older MF prime 

WITH a solid infinity stop costs less than the 

lens hood for that fast zoom. Common sense ?  

   

   

  

`

[Aquilla]

Don’t know what ‘OP’ means, I don’t know about common sense either where’s the point in buying another lens when I already have this fantastic one . If you can’t offer constructive help then don’t bother replying.

[tinplater]

I believe if you set to manual focus, then adjust until the stars appear like tiny pin points, you should be fine.

[Aquilla]

Brilliant, will give it a try as soon as we get a clear night- thanks for you advice

[bobbyroe]

Depending on which camera body you're using, and your focus settings, you may see a distance scale on the LCD screen or in the viewfinder when you focus. I know I get one on the A7RII with that same lens. The technique that's worked very well for me is to turn the focus barrel from a near distance setting just barely until the ∞ symbol appears. Of course, that's assuming you don't have anything bright enough to visually focus on. Another tip: visually focus at 70mm, and then adjust the zoom setting (e.g., to 24mm) and the focus is retained. You may find that temporarily setting the ISO very high (e.g., maximum for your camera) helps with focusing, then set ISO back to your preferred value before shooting.

[Username]

Don’t know what ‘OP’ means,

 

I don’t know about common sense either

 

where’s the point in buying another lens when

I already have this fantastic one .   

 

If you can’t offer constructive help then don’t

bother replying.

   

Apparently you don't know much. And 

this reply is constructive help. Use it. 

[holmes4]

Don’t know what ‘OP’ means,

 

In the context of forum threads and similar, it means "Original Poster" - the person who started the thread (you).

[taoufik hl]

i have the sony 24-70mm GM and i cant focus to infinity  i only focus on 8metre

can any one help

[XKAES]

You really do need to manually focus in this situation, but with long lenses you can't rely on marking on the lens or in the camera.  You need to do it visually -- and you gotten some mostly helpful suggestions.  Focusing on the moon is great -- if it's available.  Two more tips.  Make sure the diopter adjustment for your viewfinder is correct for your sight FIRST.  Also, consider buying a viewfinder magnifier -- Minolta made several that fit on Sony cameras (Sony bought Minolta).  I use a Minolta AngleFinder VN on my a850 which has 1X and 2X magnification.  Minolta made other magnifiers as well -- a whole lot cheaper than a new lens!

Also use a good tripod and cable release/remote.

And for the best results, stop down -- but that depends on the lens and the situation.

And if you like the results, you might decide on a longer lens, but most of my best star shots were taken with wide-angle lenses and some foreground in the picture.