Recent content by Dangerous_Dave

Sigma 17-50 image quality is top notch, up there with Leica lenses I have owned. It is supposed to compare favourably with the Canon although I have not owned the latter. Pity it wouldn't autofocus.

Hi folks. I have recently bought the Canon EF fitting Sigma 17-50/f2.8 as I read some rave reviews about it. To be fair it is a great, sharp, fast lens. The trouble is it simply will not autofocus on either of my DSLRs (EOS30D and EOS20D), it hunts back and forth before eventually - if at all...

I think there are two issues here. 1. Optimisation for the sensor size 2. Mirror clearance EF-S lenses cannot be used with the 1D and 5D (and 10D) as they obstruct the mirror. Sigma DC (dunno about Tamron DiII) are OK in this regard, but are optimised for an APS-C sensor so you won't get very...

Umm...just been thinking about this and isn't it the other way around? I know film grains are generally larger at 10+ microns but they don't work the same as pixels eg aren't superimposed by a bayer matrix. There is also the cost issue - for the price of a full frame DSLR you could have a large...

Thanks again for the replies. Yes, the plan was a mechanical shutter SLR. As the plan was to use it purely for bulb shots, the metering is a minor inconvenience. After posting, I sent an email to SRB Griturn and received a very helpful reply from their technician Ian Broomhead: So plan B...

EOS20D - old hat and a bit noisy basically. I ought to upgrade, but I would need to budget x+£200 for astronomical modification.

Second hand film camera, roll of film and processing. Jobsagoodun. :thumbs:

Thanks for the replies. As it happens, I scored an EOS300 for pennies off ebay the other day, which I am going to use to get my bearings with film, but I was really after something 'battery-free' as back up on a trip to shoot the aurora. My DSLR batteries run flat in no time in those...

Has anyone managed this? I have been right round the internet and not been able to find an adaptor. I know it is generally a daft idea as most EF lenses lack an aperture ring etc, but I own several manual EF lenses (Samyang, Zenitar) for long exposure work as well as a range of adaptors for...

I've got the 8mm and I think it's a cracking lens for the money. I expect there are better fisheye lenses out there, but not for <£250 bn. http://www.flickr.com/photos/dangerous_astro/4719988767/in/set-72157607475934651

Here's a tutorial I wrote for Astrochat: http://astrochat.co.uk/forum/viewtopic.php?t=7518 Examples of my star trail pics here: http://www.flickr.com/photos/dangerous_astro/sets/72157607475934651/ Hope that helps

Following a Google search, they seemed to be the only UK company who stock a part for one of my telescope mounts. I kept trying to submit an order and kept getting my card declined... So I have to "co-ordinate with my bank" because they can't handle 3d verification on a credit card.:clap...

Nothing decent! I think your best option would be to look for a second hand ED doublet like the Skywatcher 80ED, William Optics Megrez 70 et al. You would still have the issue of finding a sturdy telescope mount to carry it but if you are content photographing the moon, you shouldn't need to...

John mate, we had this discussion on Astrochat and IMHO you are simply not right with that low ISO theory. As you know I've done a lot of this stuff in practice, with my 20D and Vixen GP mount and found the optimum ISO to be 1600. In my experience, you should use the highest ISO you can get...

Hi folks, does anyone know whether/where I can get hold of a Pentax 67 to T-thread (T2) adaptor? I've found plenty of different flavours of bayonet fitting adaptors for Pentax 67, ie on ebay and my favourite photography stockists, but not found anything with a T-thread. If all else fails...