Single shot test

[Catsick]

Ok, very much the beginner and restricted to a 75-300 lens using manual focus, f22, 1.6sec exposure, attempted stack from 10 images using DSS. Cropped image to the main subject which suprised me how much it picked out, altho possibly Rubbish compared to what others may be able to get.  No longer looking at a telescope, possibly still after a mount but may be looking into tele extenders or an 18-270.  The 50-500 is tempting but a bit pricey!

And as you may guess,  I have no idea what this is other than being in the vicinity of the Plough last night.

[Catsick]

Damnit, can't edit thread title! Wasn't a single shot...

[Owmuchonomy]

No idea what you've captured there.  What did you focus on?  Also, you should try and image with your lens wide open, or almost wide open.

[Catsick]

I think a lot more practice is on the cards!

2 possibilities, either it is something really interesting which  I highly doubt now or it is some really embarrassingly stupid mistake for someone to make lol

[Leveye]

As stated above don't use an aperture that small. Use the lens wide open for the most part. This shot looks something was moved or bumped while the exposure was being taken.

[Catsick]

Think I'll give the 50mm 1:1.8 a try if it stays clear this evening.  I don't know where I picked up the idea that the aperture had to be high from but it has lead to my undoing for now.

[hobsey]

Think I'll give the 50mm 1:1.8 a try 

Good choice.

I'm watching about 5 of them on ebay at the moment.

[Catsick]

Good luck getting the lens.

[hobsey]

Cheers, I'm going to need it. Keep getting out bidded.

Looking forward to seeing your single shot with that lens.

Just been reading up on Milky Way photography.

[Catsick]

Unfortunately had a go last night and it looks like my lens might be faulty, wide open lowest aperture etc and stars look more like chevrons...

[hobsey]

Oh, not good.

With the lens attached to the camera, see if you can see all the aperture blades move when you adjust the aperture settings.

[GuillermoBarrancos]

You don´t really give us much information.

What brand camera are you using?

What brand camera lens are you using?

Most important: What Object were you imaging?

By Your description it sounds like you are imaging with a DSLR and regular zoom camera lens? Then Your F ratio value doesn´t sound right. As I never seen a regular camera zoom lens with an F22 f/ ratio. Or any camera lens for that matter. Even cheapest of the cheapest zoom lenses still have around F/5 - F/6 ratio.

[Catsick]

Original images shot with a Canon EOS550d using a Canon 75-300mm set at max zoom f5.6 with the cameras aperture set to F22, auto iso, 1.6sec shutter.

The 50mm 1.8 I tried wide open on both the lens and camera but it's causing issues.

[frugal]

If you have stopped you lens down to f22 then you have 1/64 of the aperture area than you do when the lens is wide open. So you are going to need to expose for 64 times as long to get the same amount of light in.

If you have stopped the lens down to f22 you will also be getting diffraction patterns from the blades on the aperture. If you have a 6 bladed lens you will effectively be shooting through a really small hexagon at that f stop. So you will get lots of 12 pointed stars.

From listening to other people. The Canon f1.8 50mm lens works best at about f4. That way you are still letting in lots of light, but you do not get as much aberation near then edges of the frame.

Sent from my SM-N9005 using Tapatalk

[DaveS]

First thing to do, turn off any auto settings. Use manual mode and raw. If you haven't already got a remote release get one now. or else use APT and your laptop.

And start looking for manual lenses. They don't have to be Canon as you'll be doing everything manually. Old vintage pentaxes, Nikons or Olympus OM are worth looking at, but NOT Canon FD / FL as the back focus is too short.

[Catsick]

Any shots like this  I always do manual, but think I may have found the issue although I'm guessing as cannot check right now.  The 50mm fully open, but with the camera aperture set high F10+ I think cleared up the chevron pattern however I may have  carried that onto the larger lens as well rather than leaving lens & aperture open but increasing the ISO.  It gets tricky when you start messing with how much light you let the lens accept whilst changing a similar setting on the camera... never simple is it!!!  Good job I didn't get a telescope......... yet

 It's never simple is it, what works with one lens doesn't necessarily work with another.  As for the mirror lens, that's a different matter altogether!

I have got a remote for the camera so no contact is made whilst it's shooting although the tripod I have is Rubbish so this probably contributed to the iffy image in the OP.

[dph1nm]

Original images shot with a Canon EOS550d using a Canon 75-300mm set at max zoom f5.6 with the cameras aperture set to F22

I am confused. How do you set the camera aperture different from that of the lens? If you set the camera to F22 doesn't it stop the lens down to F22 automatically?

NigelM

[Catsick]

Nigel, my mistake, I'm seeing the 2 things as separates when they're not, not a good day today!