UV Unwrapping and Minimize stretch problem

I have been trying to learn uv mapping in blender.

Now when I follow an old tutorial this is where I come and get stuck

The object is an eye and I have marked the seam at the rear of the sphere.

When I press ctrl +v minimize stretch feature starts happening and I come up with a result which has a very stretched out area near iris. Meanwhile in the tutorial it is crystal clean without any stretch.

What exactly I am doing wrong and how can I fix this stretching issue?

Old tutorials… Well, things tend to change. You can get decent results by just a default Unwrap (1) and if you’d like to distribute map differently use Proportional scaling of the center point using Linear falloff in UV editor (2).

Yes. it’s simply better to use the general unwrap operator available in the UV menu (U-key), as the minimize stretch algorithm that Blender uses is a bit crappy (as you can see in your image where it didn’t even produce proper spacing for all vertices).

Well the tutorial specifically asked to switch off the proportional editing tool by pressing O

I need to mention the front is not normal sphere but Iris is inside like a cylinder.

screenshot attached

Ok I will keep that in mind but if for some reason even that gets stretched out, how exactly do I add new vertices in the web of vertices?

I did a normal unwrap first which gave me a star figure, I scaled the inner circle loop to stretch it out till the end and then pressed ctrl +v.

To use the unwrap operator properly, you need to make use of seams on the model so as to create islands.

Without islands, you will get a situation where faces in areas are pinched very closely together because it’s trying to unwrap a surfaces that almost completely closes in on itself.

I would probably place a seam on the last loop of the back of the eye model (before the vertices merge), the first loop in the front, and one of the lateral loops. You should be able to get a nicely unwrapped profile when you invoke the operator.

It could be useful to know which is the tut you follow…
However as i get it - part which is pulled in will be pitch black, yes? Also, since this is an eye - back of it - 1/3rd at least wont be visible assuming this ain’t a caricature or horror story? Then if you put seams and select just part which needs to be unwrapped you’d get something like this. Btw, if you then paint lover left one pixel black…

Edit: did tut ask for switching off Proportional edit in UV Editor window? I did not mean 3d view.

Well in the tut it asked me to select only the edges at the rear for seam, shown above as red in the black wireframe.

yes in the UV editor window.

Tutorial is from old book :Blender for dummies, the first edition of 2011.

The tutorial might actually have misleading information then, if the UV map contains a region where the surface in general is concave in nature or have parts that turn back into itself you will get major pinching issues in the UVmap as seen in your original image.

Tutorial is from old book :Blender for dummies, the first edition of 2011.
For UV unwrapping the tutorial that old should still be suitable to use. Ensure that you are following it correctly.
With UV unwrapping there are many alternative solutions, you need to understand the basic concepts involved with UV unwrapping which will then enable you to use on any future model. If you’re struggling with this object then go onto a simpler model first. Also remember that you don’t have to unwrap the whole object in one go, you can select faces and unwrap those differently to other face selections. What we have since that tutorial are better tools to then stitch these unwrapped islands together

yes it might have concave surface in the front.

Thanks Richard

Can you give me a link for a proper tutorial for UV unwrapping?

In the book I have learned the steps of unwrapping, baking and applying textures, but I am not able to understand the concept of unwrapping and how exactly to figure out what exactly is the problem (if any) with the uvs…

Was this the tutorial you have followed? http://blenderbasics.com/unwrapping-your-eye-and-painting-a-detailed-texture/

yes this is the tutorial, though cycles part is missing in the book.

I think I need to buy the latest edition which was published this april.

hi sorry for disturbing i am new to blender and to this site that is why i didn’t know how to make a forum but i find this onesome haw relevant to my problem i started UV mapping learning from a tutorial you can find on youtube with the name
Blender modeling and texturing simple medieval house / Blender - středověký důmhowever i was going well untill i pressed f12 to see the disaster[ATTACH=CONFIG]399194[/ATTACH]
the render looked horrible in render but it looked good when i pressed shift z

so i would really appreciate an answer thanks for advance

Well, i’m certainly not a pro and do not write books but i’ve never seen such UV unwrap approach during the course of Blender changing versions from 2.49 to the latest.
Unfortunately, after briefly googling around i can not recommend any written tutorial which is detailed, explanatory and covers eye unwrap/texturing using Blender 2.7x - better substitute for the one you follow.
I can only offer to look into images posted and use this type of unwrap to further follow the tutorial - vertex painting, baking, manual texture painting. You could try this in a new blend file and if there are any questions just post them.

If you intend to paint the eye texture yourself, you can get away by just making sure you have UV islands that don’t overlap each other followed by simply painting (you can use the stencil brush to apply reference textures to various spots if needed).

sorry double post.