Gerd Waloszek       

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DSO List (Rich-Field Objects)

Introduction | Introduction | Overview of Rich-Field Objects | References

I compiled the following list of rich-field objects* using the Deep Sky Reiseatlas (Stoyan/Feiler & Noack; see references).

*) Rich-field (deep sky) objects denote in the case of my list:

1. large DSO of an extension of more than 1.5° and
2. at least two DSO, which are located within a field of view of up to about 4° and thus, can be observed together with corresponding telescopes (low magnification, large field of view).

This list should help me - and maybe others - to select rich-field DSO for observation. The rankings from the Deep Sky Reiseführer/Reiseatlas can be a further help when selecting the objects.

Introduction

At the beginning of December 2019, a starfriend of mine had suggested in a forum of the astronomie.de Website to create a list of rich-field DSO, in order to be able to observe these objects specifically with his "rich-field telescope." This includes on the one hand large DSO, which can also be larger than the field of view of a telescope, and on the other hand several DSO, which can be observed together in the same large field of view. It was not exactly defined and also depends on the equipment available, how large the field of view actually should be. Many astronomers have contributed objects to the discussion from their own experience, so that the list grew and grew.

I, however, decided not to participate in this discussion, and to go my own way. This is to browse the Deep Sky Reiseatlas (Stoyan/Feiler & Noac) page by page for DSO that fit into a field of view of about 4° (the Telrad circles in the atlas helped me here) and can thus be observed together. I left out or added to the list one or the other object that did not exactly match these criteria. Certainly, I also made some mistakes, which I hope to be able to correct in the course of time.

First of all, I created an Excel list, because this allows to filter the list according to certain criteria and thus, to find specific information more easily. Nevertheless, I also created a static HTML table for my Website to make the list accessible to others, even if I have to correct the list manually again and again...

Examples

The following examples are intended to illustrate the principle, but were created with the SkySafari 6 application for copyright reasons. The red rings are the Telrad circles (0.5°, 2° and 4°).

M 36 and M 38 fit into a field of view of 4°		Ditto, larger sky section
Perseus Double Cluster and Muscle Man fit into a field of view of 4°		M 36 and M 37 just fit into a field of view of 4°, larger sky section
The Hyades (Mel 25) are too large for a field of view of 4°		The Pleiades (M 45) even fit into a field of view of 2 °

(Images Courtesy of SkySafari Astronomy, www.simulationcurriculum.com)

Eyepiece Selection

In the following, I list the data of my telescopes that are "just so" suited to rich-field and long focal length eyepieces. The TLAPO1027 and the Explorer 150PDS, which I sold in January 2020, can perhaps still be considered as "rich field" telescopes, the Celestron C5 with reducer/corrector with a maximum FOV of 2° probably just so (it is sufficient for the Pleiades M 45).

Italic: 2" eyepiece; Gray: no longer in my possession

Conclusion: I achieve a FOV of about 4° with the PS 72/432 using the 26 mm-2" eyepiece, and with the TLAPO1027 using the 40 mm-2" eyepiece; with the C5R I only achieve a FOV of about 2° at maximum.

Overview of Rich-Field Objects

Notes: An object group always starts with the first object of a constellation and ends before the next constellation. Not all objects in a group may belong to the same constellation. In such a case, I added the corresponding constellation in brackets.

I have already observed quite a number of DSO individually and note this in the table; I also note when I observed this with the StarTravel 120/600, which I had borrowed in autumn 2019..

Legend

*) Page in Deep Sky Reiseatlas (see references)
PN = planetary nebula, GE = galactic emission nebula, GR = galactic reflection nebula, OC = open star cluster, GC = globular star cluster, DS = double star, SP = star pattern, SC = star cloud
ST120: many first observations were made with the StarTravel 120/600 (ST120) refractor

References

Books

• Michael Feiler & Philip Novak (2014). Deep Sky Reiseatlas, Oculum Verlag
  www.oculum-verlag.de/detailview?no=2014
• Ronald Stoyan (2014). Deep Sky Reiseführer, Oculum Verlag
  www.oculum-verlag.de/detailview?no=2015

Discussions

• Auf der Suche nach Richfield Objekten (VisuSCor): forum.astronomie.de/threads/auf-der-suche-nach-richfield-objekten.281222/#post-1432692