MarkAR

A DIY counterweight bar and weights are a fairly easy project if you have a lathe, a pillar drill and a few other tools. Could be an interesting little project.

The bar might  have to be something like chrome alloy steel with all the weights hanging off.  Possibly even go up to 30mm depending on how and what is attached at each end.

Large diameter stainless steel rounds are pretty expensive, smaller diameters could be drilled and filled with lead. Delrin could be used with lead slugs, they won't rust.

Attaching the saddle to the shaft so it doesn't come loose has various solutions, threaded in with a locking nut, cross pinned, loctite...

The main question, is it worth the faff in time and effort or easier to pay the 169 Euros.

Stunning image.

Superb.

Heres what it looks like with nothing to diffuse the screen.

1 hour ago, PeterCPC said:

I can't see why you want the plastic disks at all. Why not just do as Olly suggested.

Peter

I think without the disks, the white screen would be too harsh and needs some diffusing. Will take a couple of test shots later.

Check out AstroBackYard on Youtube, some really good advice on filters. 

https://www.youtube.com/watch?v=FDim3HHq7rk

https://www.youtube.com/watch?v=hFq-y8wTp9o

Costa Rica is lovely, so much wildlife to photograph as well.

1 hour ago, ollypenrice said:

Could you not just stand the light source at right angles to the lens and a small distance away from it? Do you really need to attach it?

Olly

Hi Olly, that's pretty much what I was planning to do, hold the laptop up to the lens. It's finding something suitable to hold the opal plastic disks to the lens hood that's the problem. Saying that I have an idea which might work.

How about putting 4 pins or 2 curved pieces to hold the opal sheets on the front, the pins or curved pieces would sit over the larger petals top and bottom and not get into the field of view. Might try that as I don't think the Samyang hood will fit.

I would definitely get the modded 60D, factor in the cost of the filter included and it's cheaper than the 600Da.

WOW!!! Very nice details.  

That could work, although I've just found that Samyang do a filter holder.

https://www.ebay.co.uk/itm/Samyang-SFH-14-Filter-Holder-for-Samyang-14mm-F2-8-ED-AS-IF-UMC-MF-New-UK/223852374043?hash=item341ea4281b:g:KHIAAOSwsFZeHcWS

Add 2 sheets of 3mm opal and hopefully that might be enough. Can always dim the laptop screen or sandwich on another sheet.

I'm presuming that the lens hood on the 14mm F2.4 is the same as the F2.8, can't find anything more specific.

Any machine shop will be able to open it up to fit quite easily, if you were closer to Guildford I would say pop round and I'll stick it on my lathe.

Looks like it just needs boring out to around 2.5 inches.

Hi All, I have a Samyang 14mm F2.4 lens that has a fixed petal shaped lens hood.

My initial idea to take flats is to get  some opal plastic disks, maybe a couple of 3mm think and a 5mm thick one and shooting at my laptop screen set to white.

https://www.cutplasticsheeting.co.uk/frosted-acrylic-perspex-sheeting/opal-frost-acrylic-sheeting

Trouble it on how to attach the disks to the lens hood, some sort of rubber slip on boot ???

Anyone any other Ideas on a set up to take flats with this lens?

Some good detail, can't wait to see the finished image.

On 07/02/2020 at 15:34, Nova2000 said:

Which light pollution filter will be the correct match with a unmodded camera to image targets in close to natural colors ?

I looked into this myself a couple of weeks ago and from all the reviews I found online  it seems that the Optolong L-Pro has the least tint.

Thank you all for the warm welcome, shame the weather isn't as pleasant.

Lovely image, I like the halos but wonder if they could be softened just a tad to eliminate the stepped look. No idea if that's possible or not.

I particularly like the 3rd image, lovely crisp craters.

Very nice, lovely colours.

2 hours ago, Rusted said:

Thanks. 

The plates were mostly cut out with a powered jigsaw, lubricated with lamp oil [UK: paraffin] and then filed straight by hand.
Only later did I obtain a sliding, 12" DeW, miter saw which could manage aluminium with far greater speed and accuracy.
Cut-offs up to 6" [or so] were relatively painless, even in 20mm thick alu. But I never had the nerve to saw the long sides on my table saw.
Besides, DeWalt specifically warns against such use. The problem with sawing aluminium with a circular saw is the swarf.
It flies everywhere and can't be easily collected. Non-magnetic and a shop vac with "turbo" sawdust separation might be damaged.
So I had to use a dustpan and brush over several months until it was mostly all gone.

Dedicated metal working chopsaws run at a lot slower rpm than woodworking ones, swarf will still get everywhere but not so extreme. A powerful vacuum cleaner definitely saves time, I use a 1400w one that really sucks 🙂

Regarding the poorly machined worm wheel, I hope you kicked up a big enough stink to at least get a partial refund and also well done for making it right. 

Both great images, the rework has a little more vitality and a slightly "stormier" feel about it. The original a little more peaceful looking.

25 minutes ago, Stu said:

Welcome to the forum Mark. Not so far from me, Walton-on-Thames. Some decent dark sites on the South Downs for you to head to.

Cheers Stu, looking at light pollution maps it does get down to Bortal 4 a little further south, hope to find somewhere not too far away where I can park up away from the glow a bit, looks like there are quite a few choices of commons to visit.

An excellent thread, I do a little hobby engineering occasionally and can really admire the work and thought that goes into a project like this.

Hi All, after taking a few photos at pretty short exposures, Ive decided to invest in a tracker to get me started properly.

I initially was going to get a Fornax Lightrack 2 and their wedge with an iPolar and a Tracer battery (total around £1100) but then thought it might be overkill to start with and not so easy to pack for holidays. Although it is more accurate.

So I think I'll invest instead on the IOptron Skyguider with iPolar kit (£499) and the Williams Optics Wedge (£189).

My current photography kit is:

Canon 80D

ThreeLeggedThing Albert tripod and Airhed Pro ball mount

Canon 100-400mm F4.5-5.6 IS 1

Sigma 24-105mm F4 ART

Sigma 30mm F1.4 ART

Samyang 14mm F2.4

Living under Bortal 5 skies I thought an Optolong L-Pro clip in filter might be a wise investment so have ordered one from Laida Optics off AliExpress for the bargain price of $142.55 plus a massive wait for shipping.

Possibly in the future I'll look into something more substantial  like a GOTO mount.

Hi All, I think I caught a bug taking pictures of the Aurora Borealis in Tromso whilst up to knee deep in snow.

Tried taking shots of the moon and some stars with a little success so have decided to get a tracker for longer exposures and see how it goes.

I've been doing a lot of searching and found a whole load of information to get me started on the basics, now to put theory into practice.