wulfrun

I was in my mum's garden, set up with a film camera, the longest lens I had (probably a 210 and maybe a 500mm) and a welders glass gaffer-taped over the objective. Shot most of a roll of slide film, something like 2 or 5 minute intervals, can't recall. Yes, I did peek through the glass (didn't know any better) to determine when to start shooting. In my defence, it was a film SLR with a metal-bladed shutter so worst-case I might have melted the film if my "filter" failed.

We weren't quite in totality here but it was a warm, cloudless day (unlike Cornwall!). At maximum eclipse it went really dull and was distinctly cooler & had a very eerie feeling.

Nice find. I used to collect former-USSR rangefinder cameras (yes, niche maybe!) and still have several. They often get slated for poor production quality, sometimes justifiably but their optics were always good designs by the contemporary standards. I still have quite a few lenses and they produce excellent images.

Your bins possibly won't be multi-coated but I bet they perform really well. Enjoy!

22 minutes ago, SthBohemia said:

Looks more like a Dob missing a stabilizing support making it inherently unstable? Although the OTA only weighs 3.6Kg it is reasonably long for the tiny bracket that supports the scope to the single arm looks (2 me anyway) insufficient to hold the OTA steady...

There are several similar designs and I haven't noticed complaints about lack of stability. Personal experience with mine suggests the mount is quite adequate, provided it's placed on something substantial. On a wobbly table, well no surprise it'll be wobbly.

39 minutes ago, Zeta Reticulan said:

I don't know how heavy the 150P OTA is. As Dob' mounts are basically made from old banana crates the OTA on its own may well exceed 5kg. Which would explain any vibration return issues.

The mount is pretty solid board. I've just weighed mine at 7.45kg total, with finder but no EP. Just the OTA + finder comes in at 4.05kg, so the mount must be 3.4kg. Add a hefty EP and it's pushing the limit.

11 hours ago, SthBohemia said:

^ Very little to none!

That said, achieving such is rather expensive. Unless of course, you wish to 'cough up' a large pile of 'loot' for a Losmandy, Astro Physics etc etc mount. Maybe your best option is to make yourself a Dobsonian mount, little expense for a good rigid mount. There are threads within SGL pertaining to DIY Dobsonians.

Unless the OP bought the tube only, the Heritage 150P is already a table-top Dobsonian (ok, not quite, to be pedantic, since it's a 1-sided mount).

I was out with the binoculars and in the recliner at a similar time and saw something bright fly through the view. Far too fast for a satellite (which, by chance, one was also one passing through!). From memory, at the time I was looking somewhere in Cygnus, so a Perseid meteor would make sense and could well have been the same one. I did look around but saw nothing more of it.

30 minutes ago, thestargaze said:

Can you recommend some good but not too expensive eye pieces? I was looking at the StellaLyra line at about 50 pound a piece but if you say they are not good enough.., 

Usual recommendation for good value is the BST Starguiders. The  5, 8, 12 and 15mm are well regarded, the 18 & 25mm folk say aren't as good. I only have one, a 5mm and I find it good (I'm using different scopes though). You have other suggestions above. Definitely keep the 30mm if you like it. Why change what works for you.

EDIT: I can't comment on the Stella Lyra EPs, I know nowt about them.

The atmosphere plays a big part in what you get to see on any night. Your 8" dob is well capable of showing a great deal but conditions need to be right. Patience is something you'll need in spades! If you're looking at (say) Jupiter, look at nearby stars too...if they're twinkling madly it's a sure sign views will be poor. Always best to wait until things are as high as possible too, you'll be looking through less atmosphere. And you need to hold the view, not take a quick glance. The longer you look, the more you'll see. Your brain starts putting together the details that are there, fleetingly, in the moments that the view is steady.

The eyepieces supplied with scopes are usually mediocre at best, so worth upgrading as soon as you can afford it.

Here's an excellent guide to collimation, without making it too complex or technical:

https://garyseronik.com/a-beginners-guide-to-collimation/

Above all, keep going!

11 minutes ago, Neil H said:

If your quick Stu is selling his heritage 150p look in the for sale section 

OP doesn't yet have access though...

On 21/04/2020 at 09:02, Waldemar said:

Here is a way to protect your mount against wrong polarity mishaps at very low costs
You do not need to be a tech wizard to make a simple protection like this: 
https://provideyourown.com/2012/reverse-polarity-protection-circuits/

 

A bit late but since this thread has been resurrected...

There's an often overlooked and fundamental flaw in one of the circuits shown - the one that shows a PNP transistor. It's unsuitable where the supply exceeds the transistor's base-emitter breakdown voltage (which is often no more than 5V or so). A reverse supply may cause the junction to fail, resulting in transistor failure as short-circuit and circumventing the protection entirely. I feel it's necessary to point this out to anyone contemplating this circuit, it's very unwise for a 12V supply.

14 minutes ago, SthBohemia said:

For a start it's LEICA 🙂 🙂 🙂  What more can I say! Similar to having a Questar 7" Mak over an Asian made one!

You can probably find an adapter from Ebay.de, or at worst from a camera shop or Leica directly (expensive).

 

The adapter isn't just a physical adapter though. Apparently it reads a code (optically?) off the attached lens and reports it (electronically) to the body. Without this the shutter cannot be fired. This may (or may not) be a deal-breaker but OP needs to be sure else it's money wasted.

EDIT: you can read the part about the M-mount adapter here:

https://m.dpreview.com/reviews/leica-t-typ701/4

First problem will be to find an adapter to connect it to a telescope. I read on reviews that the shutter will not fire unless a lens or suitable adapter is attached, so it may not be suitable for AP at all. Someone may know of a way around that though.

You mention the solar cycle, which is pretty well known. However, from what I can find, it seems the best figure for variation of total solar irradiance due to it is 0.1% on average (with some variation, cycle-to-cycle, as expected). That makes it a negligible factor and in any case it varies up AND down rather than consistently upward.

I think the deniers have tried this idea and lost, convincingly, to the science.

22 minutes ago, Alexmar said:

So a 200FL * 5 Barlow will give-me the same image as the 1000 native FL would give. Cool.

Correct...except that the focal ratio changes too, so the image is dimmer. That's why I said you'd need to pick suitable scopes to compare. You'd need a "fast" 200mm and  a "slow" 1000mm for the exact same view.

Suppose you take your 76/300 as the example, it's focal ratio is 300/76 = f/4,  approx (which is fast). Put in a 5x Barlow and you now have (in effect) a 76/1500, which equals f/20, approx (which is slow) and the image is going to be dim.

However, if you stick to the recommended max magnification, you should be OK.

For your example scope, by the way, the practical limitation is probably going to be the size and weight of the eyepiece + Barlow that the focuser can cope with. I have a slightly larger but similar scope (a 114/500mm) and I know a heavy Barlow and eyepiece would make it sag.

A Barlow doesn't actually change the telescopes FL...but as far as the eyepiece is concerned it makes the scope behave as though it had a longer FL. In other words, putting a 2x Barlow in a scope of 500mm gives the same result as no Barlow in a 1000mm (assuming you picked suitable scopes, since the focal ratio is also affected).

I don't think there's any optical reason to pick a Barlow based on reflector/refractor BUT there might be mechanical reasons (long Barlow hitting a diagonal's mirror, for instance).

If you avoid a cheapo Barlow, you shouldn't notice a degradation in image. Loss is inevitable due to extra glass but slight.

Generally, for visual use a 2-2.5x Barlow is likely to be the most useful. Higher powers are more often used for imaging than visual. Some Barlows have removable elements that can be screwed into an eyepiece's filter threads, which results in a lower multiplication (usually around 1.3-1.5x). Meaning you get a choice of multipliers in one unit. Be aware that some eyepiece/Barlow combinations won't work like this, for physical reasons.

Give us a budget and scope/eyepieces and someone will soon give you decent options & opinions.

29 minutes ago, Zeta Reticulan said:

If anything lands in my backyard I'm keeping it.

Assuming you still have a backyard to keep it in...

Just to throw in another idea...OVL Nirvana 16mm plus a 2x Barlow. Not much more money than two BSTs.

It'd give you your 25mm, 16mm, 12.5mm (effectively, with 25mm + Barlow), 8mm (effectively, with 16mm + Barlow) and the 5mm BST you have on its way. The Nirvana will work pretty well with the Heritage 150P and has a useful 82-degree view, better than the BSTs, meaning less nudging.

1 hour ago, Alexmar said:

At first i was looking something for about 100$(About 650 R$), but i am looking for some more expansive(200$) models like some 114mm

 

This models is a 114mm x 1000mm, it seems the brand is Golden Sun.

One to avoid at all costs. It's too short to be 1000mm unless it's a Bird-Jones (or Jones-Bird) design. No-one will have anything good to say about the design as an amateur telescope.

There's a technique to tapping too...apologies if I'm patronising you but are you using oil and running the tap back after cutting a little bit? If the tap is sharp it shouldn't take enough effort to slip in the holder anyway.

An observation: where's the fuse? If it's internal to the socket, fair enough. If not, fit one in the +ve lead. You really don't want to (accidentally) short that battery, it will not go well for whatever causes it, the leads or the battery, depending on how caused.

The moon's visible in the daytime, some of the time. The sun is also an interesting target BUT you need a proper solar filter to render it safe to do. If you want your eyesight and scope to survive, make 100% sure you know EXACTLY what you're doing first. Welder's glass etc is big NO.

EDIT: I knew there was a section on here about solar, here it is:

The MA25 you have is a low power eyepiece, it probably came with scope. You could use the 2x Barlow with it but the results will depend on the quality of it and the eyepiece. Using the 5x with a basic eyepiece is probably only worth doing to demonstrate why you shouldn't have.

In theory, you can stack the Barlows but it's a bad idea and rarely done. First, each one costs you some quality and second, your magnification will be much higher than can actually be used. The view is likely to be awful.

Just to point out, a Herschel wedge doesn't work by blocking light as such. It reflects a small amount toward the eyepiece and "dumps" the rest elsewhere by redirecting it.

Hmm, I'd be very surprised indeed if a wet plug could draw enough current at 12V to do that. Is it possible it's partly shorted the centre terminal to something else on the mount? Is the plug showing physical damage? The "fault" appears to be at or close to the plug though, whatever its nature. I'd be looking elsewhere for a culprit than dew/condensation, although it's hard to say it's impossible.

EDIT: Just a thought, long-term corrosion of the plug due to repeated condensation? Is the plug normally unused?

Almost beggars belief that you can follow it manually. I think I'd be delighted to do that alone, without the complications of actually capturing images as well. Impressive result, hats off!

Having not been out "in anger" for quite a while (the weather, obviously!), I had the little Heritage Virtuoso out last night, with low expectations. Surprising it was really clear and reasonably steady. I'd been looking at the moon in the late afternoon and left the scope out in hope.

I spent most of my time looking at clusters, including the double clusters, summer beehive, cooling tower and lastly the owl/ET. All of them looking mighty fine, just using either a 16mm or 9mm all night.

I tried for the ring nebula but failed to spot it, oddly since I have (just about) seen it before despite the small 114mm aperture. Finished up on Andromeda galaxy, just a smudge but nice to see, before a cloud-enforced retreat about 12.45am.

Didn't see anything not-before-seen but after so long since decent skies I was more than satisfied!