5 replies to this topic

[slt8577]

To date, I've been doing mostly wide angle Milky Way shooting (Tokina 11-16), plus some super telephoto Moon shots (Tamron 150-600) on my Nikon D7500. I'm interested in getting a star tracker for longer exposures, but I'm getting really lost and confused in the research, especially involving weights and tripod-ballhead combos.

1. I'd welcome any input on a SkyGuider Pro Camera Mount Full Package vs. a Star Adventurer 2i Pro Pack for my needs.
2. As a first step, am I needing to make sure my camera body with battery plus my biggest lens is below the payload of the trackers (w/ room to grow in case I upgrade to full frames)? Right now, I'm counting the camera+lens as roughly 6 lbs, and I have the max payloads of the SkyGuider and Star Adventurer as 11 lbs each.
3. For the tripod-ballhead combo, am I needing to make sure that camera body with battery plus biggest lens, plus the entire tracker kit (including counterweight) is less than the payload of the tripod-ballhead combo (with room to grow)? Right now, I have the SkyGuider package as 3.2 lbs and counterweight at 2.97 lbs (6.1 lbs total) and the Star Adventurer package as 3.63 lbs and counterweight at 2.85(I think) lbs (6.4 lbs total). So, adding the 6 lbs of camera and max lens, the ballpark payload of the tripod-ballhead combo would then need to be absolute minimum 12 lbs--is that right?
4. Given all that, any recommendations for a good tripod/ballhead combo that would support the above (w/ room to grow)? Ideally, I'd really like to be able to put this tripod in a standard suitcase, so that would make the folded height less than 24" (ideally maybe around 20"). I'd also like to use this as my primary non-astro tripod as well. Looking to spend $100-150, new or used, but I don't know if that's feasible. Could I get away with something travel-friendly like this Neewer (which lists a 33 lb load)?

 

Any advice and suggestions would be much appreciated!

[polslinux]

Hello! I have the same gear as you (as you can see on my signature). Here's a breakdown of the weight:

SkyGuider Pro Pack:
  SGP:                          0.97 kg
  counterweight:                1.35 kg
  counterweight:                1.35 kg
  dec bracket + rod +
    pano head + tripod plate:   1.05 kg
  WO latitude base:             0.99 kg
                                -------
                                7.06 kg
Imaging setup:
  Nikon D7500:                  0.68 kg
  Tamron 150-600 G2:            2.06 kg
  Tamron Lens Hood:             0.12 kg
  William Optics DSD210:        0.25 kg
  Dew heather:                  0.05 kg
                                -------
                                3.16 kg

WO Uniguide 50mm/f4:            0.52 kg
ASI290MM-Mini:                  0.06 kg
                                -------
                                0.58 kg

Main system + guiding:         10.22 kg  # total weight on the tripod

Imaging setup + guiding:        3.94 kg  # total weight on the SkyGuider Pro

I have yet to test it with the guiding system (is on its way), but I have seen a lot of people using this payload (and even more, around 4.3kg) with success.

The key factors with such heavy payload are:

1. balance. This must be perfect (neither front nor back heavy and a little east heavy during the whole session)
2. guiding, especially at a long focal length (>350mm)

Up until now I've been using the SPG with a payload of 3.36 kg without guiding, and I've managed with success 90s exposures at 400mm, but I usually keep my subs at 75s@350mm unguided (to be on the safe side).

 

Previously I was using this (https://www.amazon.c...t/dp/B08CR77B6M) tripod, but when I switched to the Berlebach things became a lot more reliable and easy. Do not underestimate the importance of a solid and stable tripod, trust me, I've been there

Edited by polslinux, 15 December 2020 - 03:57 AM.

[the Elf]

Think twice where you want to go finally. If you want to shoot deep sky objects with a long focal length you need to use a sturdy mount. The big advantage of a tracker is it's low weight so that you can use it on a hiking trip or take it on an airplane. Compared to a mount there are a lot of cons:

- payload is very limited

- there is no goto, you have to find the object in the sky

- if it can be guided the guiding only corrects for the periodic error. Any polar error still makes the stars drift because there is only one motorized axis

- no matter if guided or unguided you have to polar align very precisely

- the periodic error is high. A mount may also have a high PE but many have a correction for it, called PEC or PPEC for (permanent) periodic error correction.

Basically that limits the focal length and the sub exposure length. Unless you want to use it during hiking or for wide field shots only a mount can do a lot more for you. The premium trackers are in the $500 range, a good beginners mount like the EQ6-R is about 3x the price. What you can do with it is so much more. It will serve you for many years. An 8kg setup at 1100mm focal length is not a problem at all.

The EQ6-R comes with a camera trigger port. It supports time lapse. It comes with PPEC so that you can shoot unguided with a medium focal length.

Don't get me wrong, not telling you what to do. I just want you to make a well informed decision. Stunning images can be taken on a tracker but the selection of objects is limited compared to a mount.

[polslinux]

I completely agree with you Elf, a sturdy mount is must in this hobby
When I started some months ago, I wanted something small and cheap, because I wasn't sure this hobby was for me. But now that I am totally sure that I love DS imaging, I regret not having chosen a more capable mount. I mean, nothing wrong with the SGP, it's a little beast, but having to deal with carefully planning every purchase due to the weight limit is a major pain.
Up until now, I didn't have any issue framing my target using a 400mm FL on my APS-C camera. Plate solving is definitely a must at such high focal lengths, especially for non-goto mounts.

BTW, I have the CEM40 on my to-buy list (although only for 2022)

[fewayne]

I chose iOptron's CEM25P for precisely these reasons. At 10 lbs. for the mount head (plus tripod, plus counterweight) it's not what you would call backpack-able, but it's easy enough to lug and set up. It will carry 12-15 pounds pretty reasonably, has full GOTO and can guide in both axes. Center-balanced equatorials are considerably lighter, per pound of payload weight, than traditional ones. I was looking at trackers at the time but decided to stretch for the few hundred extra bucks. Really glad I did. Mind you, I'm imaging at 400mm or less.

 

Usually the ballhead goes on the tracker's drive, you don't mount the tracker on a ballhead. That would make polar alignment unnecessarily frustrating, for one thing.

[joeytroy]

slt,

 

I started with a SGP and was very unhappy with the results even though everyone on YouTube was showing amazing tracking and capture at 4 minutes with a RedCat 51 and DSLR. I could never get it past 40 seconds without star pull. After contacting support there was an issue with the mount moving to quickly in a full 360 degree rotation in 22 hours instead of 24 hours. I ended up sending it back to and moved to the Sky-Watcher EQM-35. Based on the SGP, William Optics Vixen bar and also a tripod I was going to need to purchase the mount would have costed me over $900, the EQM can handle 22 pounds and will allow me to upgrade if I ever move out of the RedCat 51 and was $725 on Amazon, it's gone up in price but if you look at OPT or other vendors they have it at the price just not sure on stock. Here is a blog post I did on both with the pro's and cons. With the money I saved I set it aside and bought the ZWO ASI Air Kit and can now polar align, track, dither, and shoot objects from the comfort of my couch using my iPad and not freeze outside.

 

SGP M45, M42, M31

https://joeytroy.com...ker-beam-me-up/

 

EQM-35 M11

https://joeytroy.com...-eqm-35-review/

 

Updated Images using PixInsight M45 & M31(what a difference an application can make)

https://joeytroy.com/pixinsight/

 

The one key thing I have found is you need to dither to help bring down noise and also shoot on objects a lot longer to bring out more signal. I have more posts on my blog with more details on this. Here is one on exposure time https://joeytroy.com/exposure-time/ and also an updated image of M42 at 6.75 hours on the EQM-35 compared to the 13 minutes I captured with the SGP.

 

Best of luck!

Edited by joeytroy, 15 December 2020 - 01:20 PM.