Dezerker

That definitely looks easier - thanks, and interesting to see you can control the brightness a bit by the amount that you cut out. I might try a Y-mask first just to test... Thanks again for all of the advice.

Thanks for that - I might have a crack at making a card version (no 3d printer, sadly) but otherwise the AstroKraken folks will be getting a sale! Thanks again!

Hi everyone, Do you have any recommendations for good bhatinov (or similar) masks that can be used for DSLR lenses in the 50 - 200mm range? Even with 10x live view on the DSLR, the star and spikes are too small to see reliably with the one I have currently (which is actually designed for an ED80 scope) - with my eyesight at least. I realise you can take a short exposure, zoom in on the image to check it, make a tweak to the focus and repeat until you get it, but that can eat into imaging time and all that fiddling increases the risk of nudging something out of polar alignment, so I was wondering if, and how people get around that? Any advice would be much appreciated! Dez

Thanks - it looks like a popular way of doing it - how much does it affect the balance of your setup? I'd have thought that approach would make guiding accurately slightly more challenging with the off-centre balance - does it not keep pulling one way? I'd also be worried about stressing the gears on the mount, though I guess it's not a huge weight off the side.

More googling...looks like FLO do a flatter-surfaced (and cheaper) dovetail, but it's too short to attach a guider underneath at the front. Frustratingly the longer one that might enable me to attach a guider isn't flat-surfaced. I guess I could screw the lens collar foot into the backside of a vixen dovetail (the 'wider' side) for more stability, then bolt that dovetail to a longer one that's the other way around to fit the HEQ5 head, but (without drilling holes) It's reliant on a lucky alignment of the holes to screw through to join the two together... Feel like I must be overthinking this and missing something really obvious here - how are people guiding their bigger DSLR-lens set ups on equatorial mounts?

Thanks Michael. I've had a tinker with an old dovetail today - it'll work (if I get some slightly shorter bolts than I currently have), though it's a little scary having all that weight going through a single bolt (unfortunately the lens is a loan for now, so can't drill additional holes!), and I fear you're right about the possible rotation. The shape of the tripod ring foot isn't a great fit with the raised edges of the dovetail either - I might have to look for a flatter style of dovetail if there is one. I was pondering whether using a long dovetail might enable me to fit and balance the guider underneath the dovetail at the very front, though I'd probably need a 14 inch dovetail to allow enough room between the mini guidescope, camera and cables and the HEQ5 head... Further digging has thrown up this Vixen - Arca adapter which looks like it'd be sturdier for holding the lens - but it's short, so would rule out the 'bolted underneath the dovetail' style of guiding....

Hi folks, I have a great opportunity coming up to test a Canon 70 - 200mm IS II 2.8 on an HEQ5 mount. As far as I can see the lens 'ring' (which isn't the same as the tube rings folks use for astrophotography) has a slot to fix it to an arca swiss plate, but I'm trying to find a way of attaching it to the Vixen Style dovetail bars. Can anyone recommend a way to do this? I'd also love to try guiding with this setup and have a ZWO 30mm guidescope I could use - but how to attach it to the above? Using the camera hotshoe is apparently not recommended because of potential flexure, and some recommendations seem to point to an L-bracket - arca swiss plate combos to hold the guider on one side of the dslr - which to me would surely offset the balance of the rig... The lens is quite a big old beast, so in an ideal world I'd have it 'ringed' like a telescope and attach the guider to the top of the rings....but I've not seen anyone who makes rings for this lens - though PLEASE correct me if I'm wrong! Any thoughts? Thanks in advance!

Thanks Stuart (and sorry for the slow reply) - really interesting to see, and helpful to see SharkMelley's response and links too. Was your 6d modded? I had no issues with live view prior to the modding, even 20 minute subs looked respectable (in cool weather at least), so was pretty alarmed when I saw that glow appear even on 30 second subs with live view on after modding. Like you I was pondering whether it was heat or light-leak. I'd assumed light, as I couldn't imagine how having a filter removed through astro-modifying it would suddenly affect the thermal noise, but unlike Mark I'm not sure I have the guts to bust the 6d open again and investigate possible light sources! I'll stick with turning off live view from here on! Thanks for sharing - it's super-helpful to hear others experiences and what they've learned!

Thanks David (and sorry for the slow reply), it's confusing and fascinating, I've never had a problem with live view on the 6d before the modification. I've done 20 minute exposures with live view on the 6d and the noise is still low enough to present single frames as respectable images on their own. It led me to wonder if this was a light leak (either previously contained by the now-removed filter or where something had gone wrong with the mod), but then I wasn't sure how you tell the difference between thermal noise and a light leak! And yes I have an old 600d too and it feels like it gives a heck of a kick compared to the 6d! It's significant enough to see a spike in the guiding for me, though thankfully with the mirror lockup and timer delay used together, the ASI Air seems to have time to recover the guiding before the exposure starts, which is a relief!

Thanks for this, Damian. I've had a look at this as I'd read it could be a thing, and the pattern on the dark frame seems way more 'structured' than some of the amp-glow effects I've found on my search of the internet. Spent a fun half hour in the cupboard trying different variations of covering the viewfinder, and preventing the light from the LED on the back of the camera getting in. The glow doesn't seem to be getting in through the viewfinder, so I think it must be something in-camera, but many thanks for the sense-check though.

Thanks Alan - I just hadn't thought to use the lock-up function along with the self-timer! Just tested and it seems to work. Brilliant! So regardless of the countdown I set on the ASIair, the pulse it then sends triggers the mirror lock-up and starts in-camera countdown on the camera. Thankfully the ASIair doesn't register that the actual exposure doesn't start straight away, so despite the (completely inconsequential) side-effect of having 298s exposures rather than 300, this might do the trick! Fabulous! Clear skies are forecast tonight (though currently the sky is white, rather than blue) so I'll give this a proper test. Many thanks again, Alan.

Hi All, I recently had my Canon 6d astro-modified. There is now a considerable issue with the images (amp glow / light leak?) - but only when live view is turned on when the image started. I use live view because it locks up the mirror - something my ASIair (the original model) cannot currently do. Not using live view means that shutter vibrations spoil more subs. Has anyone else experienced this? Wondering if anyone found a fix other than 'don't use live view'? Dark frames don't seem to fully combat the glow... Any advice would be great! Image of typical sub and dark frame when using live view:

Hi all, Having resurrected an old DMK 21AU04 camera, I updated Sharpcap and went outside to image the planets. On the first imaging run, it started ok, but then a message popped up saying "Writing buffered frames", and, while the software still appeared to be doing its thing, the capture didn't stop at the end of the timed imaging run, and the software had crashed - it wouldn't let me click any buttons or exit. I left it to see if it would catch up and resolve, but nothing... I'm using a reasonably swift laptop, and regardless of whether I write to the hard drive or a little portable WD drive, or what capture settings I seem to use within Sharpcap, the same thing happens? It always worked before with the older version of Sharpcap - anyone come across this before or have any ideas of what I'm doing wrong? Dez

Well I'll be.... thanks Dave. Spent longer than I care to admit trawling their website, missing this completely and getting frustrated at not finding anything!! Thank you so much for your help!

Hello folks, Does anyone know where I can find drivers for the above camera? Can barely find any sign that this camera ever existed on the likely wesbites, and sadly sharpcap can't seem to find the camera without them. Just dusting it off for a bit of planetary imaging, and possibly to use as a guide camera in the future. Many thanks!