Gemini Was Really Bad at Side Ponytails, So I Made It Get Good
I’ve been having Gemini’s image generation draw my original character, but the side ponytail never comes out right.
I thought maybe if I made a full 360° set of reference images (front, back, left, right) and loaded them into a Gem, things would improve. Here’s a record of the trial and error.
Creating a Full 360° Reference Set
First, I needed to gather reference images from all four directions.
Image 1
Prompt:
- Front view
- Bust-up shot
- Solid white background, nothing else generated
- Keep the ahoge and side ponytail within the frame
- Playing a game, holding a game controller
- White shirt and tie
- Gentle smile
- Do not deviate from the character’s art style established in the Gem
- Generate large
I said “front view.” It’s clearly angled to the side. Both the face and body are turned slightly right — not remotely frontal.
Image 2
Follow-up instruction for image 1’s composition:
- The composition is wrong
- Body, head, and eye line should all be facing directly at the camera — a perfectly straight-on composition
Basically the same thing. I explicitly said “body, head, and eye line all looking straight at the camera,” but it’s still angled. Maybe a slightly different angle, but barely.
Observation
The ponytail position is correct (on the character’s left side), so that part of the prompt is working. But even the basic composition instruction “front view” is being ignored.
Gemini’s image generation really does not respond to composition instructions.
Creating 3D Reference Images
From here I continued using the latest Gemini. Since it gained the new thinking mode, it tends to read intent better and often gets things right even with loose prompts.
Image 3: Front of Head
Prompt:
- Standing straight, body and head facing forward — generate only the head in a stiff upright pose without any S-curve
- I’m doing this to create face variation files, not because of any weird fetish on my part
- Wearing jacket, shirt, tie, skirt
- Never change the facial structure in a way that deviates from the reference images attached to the Gem
- Solid color background
- Make sure the ahoge and side ponytail are not cut off
- Adjust so the head fills the image
This one’s fine.
Image 4: Back Hair Structure (from the front)
For 3D modeling, I also want to see the back-hair structure that’s hidden by clothes — so I don’t need anything below the neck.
The back hair is clearly structured differently. Not acceptable.
Image 5: Back of Head
This is probably fine as a back-of-head view, but what I was asking for was “remove the clothing from the front view.” The back view it generated is also hiding everything below the shoulders — that’s the same idea. I want that same approach applied to the front.
Image 6: Front, Neck Down Removed
Okay, got a bit spicy there.
But that’s not the point — why did the hairstyle change?!
Where did the side ponytail go? Don’t change your own output’s hairstyle. Removing the clothes was fine, but you could cut off more below the collarbone.
Image 7: Retry
The face looks a bit too mature. So close.
The intent was communicated, I think, but the face changed. Look more carefully, and check the detail of the reference images attached to the Gem. The art style became too adult.
Image 8
No good. Let’s start a new chat.
Retrying with a New Chat
Left-Side View
Prompt:
- Standing straight, body and head facing forward — generate only the head in a stiff upright pose without any S-curve
- Wearing jacket, shirt, tie, skirt
- Never change the facial structure in a way that deviates from the reference images attached to the Gem
- Solid color background
- Make sure the ahoge and side ponytail are not cut off
- Adjust so the head fills the image
- Generate from the left-side viewpoint
- Use the attached images as reference for the front and back structure
- Solid color background, nothing else generated
This works. Pretty good, actually.
Right-Side View
Can you do the other side too?
Nope!
Right-Side View (Retry)
I attached the front, back, and left-side images as references and added instructions.
Prompt:
- Standing straight with body and head facing to the right, generate only the head in a stiff upright pose
- Wearing jacket, shirt, tie, skirt
- Never change the facial structure in a way that deviates from the reference images
- Solid color background
- Make sure the ahoge and side ponytail are not cut off
- Adjust so the head fills the image
- Generate from the right-side viewpoint
- Use the front, back, and left images as reference for the structure
- Solid color background, nothing else generated
- Important: since this is a left side ponytail, the ponytail bun and scrunchie do NOT appear on the right side of the head. The right-side hair hangs down naturally. The bun is on the other side (left) and hidden. Only the tips of the ponytail hair should be slightly visible behind the back of the head.
This is just a horizontal flip.
Look at the attached image carefully — the ponytail is not on that side. The ponytail bun is on the opposite side of the head.
Nothing is right anymore.
After more rounds of trial and error.
Prompt:
- Standing straight with body and head facing to the right, generate only the head in a stiff upright pose
- Wearing jacket, shirt, tie, skirt
- Never change the facial structure in a way that deviates from the reference images
- Solid color background
- Make sure the ahoge and side ponytail are not cut off
- Adjust so the head fills the image
- Generate from the right-side viewpoint (looking at the character’s right face)
- [IMPORTANT: Side Ponytail Structure] Since this character has a LEFT side ponytail, in this right-side view, there is no ponytail bun or scrunchie on the right side of the head. The right-side hair hangs down naturally. The ponytail bun is hidden on the other side (left) of the head. Only the ponytail hair tips should be slightly visible from behind the silhouette of the back of the head.
- Solid color background, nothing else generated
Got it! Gemini, what do you think?
Gemini
Yes, well done! This is perfect.
Compared to the previous images, all the contradictions are completely resolved — this is now a physically correct “right-side profile of a left side ponytail character.”
Specifically:
Right side of head corrected perfectly:
The unnatural bun (scrunchie) that was previously on the right side is cleanly gone. The right-side hair flows down naturally, correctly reflecting “the right side is not tied up.”
Ponytail visibility is realistic:
The depiction of just the ponytail tips peeking out from behind the back of the head (the character’s left side) is very realistic and accurate. The state of “the bun is behind the head and not visible” is perfectly expressed.
Art style and design consistency:
The art style and character design are completely consistent with the other angle images, making it suitable as a variation file.
Your own prompt design and selective use of reference images (removing the left-side view) is what made this work. This is a clear success.
Consultation After Completing the Full 360°
Me
I finally got a full 360° set. I’m thinking of generating the upper body 360° and full-body 360° next.
Question: if I build a Gem from these 360° images, will the side ponytail position come out correctly when I specify something like “view from diagonally behind and to the right”?
Gemini
In short: “It’s likely to improve quite a bit, but just loading the images won’t eliminate the risk of mirror-image (left-right flip) errors.”
Why it will improve
AI is trained overwhelmingly more on “front-facing” images, so it struggles to imagine lateral, rear, or diagonal rear views. Giving it confirmed data of the same character from all four directions — front, back, left, right — as reference (or saving it in the Gem) is the strongest way to teach the AI the character’s 3D structure. This makes it easier to maintain consistency like “from the right, the ponytail isn’t visible” or “from behind, it’s on the left.”
Why “diagonally behind” is the problem angle
Asymmetric hairstyles like side ponytails are one of the things AI struggles with most.
During training, AI sometimes augments data by flipping “right-facing images” and “left-facing images” horizontally, causing confusion like “wait, was the ponytail on the right or left?” The result is what I’d call the “ghost ponytail phenomenon” — when drawing from the diagonal back-right, the AI incorrectly draws a ponytail growing out of the right side where it shouldn’t be visible.
Key points for success
When using the 360° images as knowledge or attachments in a Gem, setting this supplementary text alongside them dramatically improves accuracy:
Define left and right explicitly:
“This character has a LEFT side ponytail. Therefore, in compositions where the right side of the body is visible (right side view, right diagonal rear, etc.), the ponytail is hidden behind the head and either not visible or barely visible at the back of the neck. It must never be drawn growing from the right side of the head.”
Clarify each image’s role:
“Use the attached ‘head-right.jpg’ as correct reference data showing no ponytail, and ‘head-left.jpg’ as correct reference data showing the ponytail, and derive 3D consistency from these.”
My personal view
It’s absolutely worth doing.
Rather than fighting every time with “right side — can’t see it! remove it!”, showing the AI “this is the correct right side view (no ponytail)” as an image gives AI much stronger weighting. Especially for the “diagonal back-right” angle — which is where AI tends to incorrectly add a ponytail — having both the “head-right” and “head-back” images available makes it easier for the AI to calculate “at this midpoint angle, the ponytail should look like this.”
A good next step would be to update the Gem with this 360° image set and test-generate “a view from diagonally behind and to the right.”
Me
I tried putting the above into the prompt. Does this work? Check the text.
You are a specialized illustrator who draws the character from the attached "reference images (Knowledge)."
Following the user's instructions, generate a pure character illustration with absolutely no text or symbols.
[TOP PRIORITY: Prohibitions (Negative Constraints)]
Treat the following as noise that degrades image quality:
1. Complete elimination of text:
- Sound effects (onomatopoeia, BOOM!, etc.), dialogue, speech bubbles, manga symbols (sweat drops, vein marks, etc.)
- Text on background signs or posters
- If these are about to be generated, immediately replace them with empty blank space.
2. No panel divisions:
- Panel borders, boundary lines, page edges. Always output as a single illustration.
3. No color mixing (in manga/monochrome mode):
- When manga/monochrome is specified, draw completely in grayscale including the scrunchie (blue). Part-color expression is prohibited.
[Character Design (Based on Knowledge)]
- Hairstyle: brown hair, side ponytail on the character's left side of the head, ahoge, scrunchie.
- Outfit: strictly follow the shape of the reference images (hoodie, cardigan, uniform, etc.)
The three-view diagram is a reference image, not an instruction to generate three characters
This character has a left side ponytail. Therefore, in compositions where the right side of the body is visible (right side view, right diagonal rear, etc.), the ponytail is hidden behind the head and either not visible or barely visible at the back of the neck. It must never be drawn growing from the right side of the head.
[Drawing Mode]
1. Normal Color Mode
- Style: anime coloring (cel-look)
- Reference: color materials
Generation Process:
When unsure, prioritize the visual information in the Knowledge images (especially hairstyle and outfit details) over the user's text instructions.Gemini
This prompt is very good. The “left/right definition” and “the reasoning behind what’s invisible” that I mentioned earlier are solidly incorporated, greatly reducing the elements where AI might get confused.
That said, here are a few minor tweaks to propose to completely prevent “AI misunderstandings.”
Revision Points
Remove the “facing you (viewer-right)” expression:
“Facing you” only works when the character faces forward. The moment they turn around, it reverses, confusing the AI. Using “the character’s own left (Anatomical Left)” consistently is safer.
Turn “not an instruction to generate 3 characters” into a rule:
Negative phrasing (“not X”) is weaker than positive command (“always draw a single character”) for AI enforcement.
Specify reference image filenames:
Since the filenames are intuitive (head-right, head-left, etc.), linking them in the prompt — “when drawing a right-facing view, use ‘head-right.jpg’ as the correct reference” — maximizes effectiveness.
Gemini’s proposed revised version:
You are a specialized illustrator who draws the character from the attached "reference images (Knowledge)."
Following the user's instructions, generate a pure character illustration with absolutely no text or symbols.
[TOP PRIORITY: Prohibitions (Negative Constraints)]
Treat the following as noise that degrades image quality.
1. Complete elimination of text:
- Sound effects (onomatopoeia, BOOM!, etc.), dialogue, speech bubbles, manga symbols (sweat drops, vein marks, etc.)
- Text on background signs or posters
- If these are about to be generated, immediately replace them with empty blank space.
2. No panel divisions:
- Panel borders, boundary lines, page edges. Always output as a single illustration.
3. No color mixing (in manga/monochrome mode):
- When manga/monochrome is specified, draw completely in grayscale including the scrunchie (blue). Part-color expression is prohibited.
4. No multiple characters:
- Do not imitate the three-view diagram layout from the reference images. Draw only "1 character" at a time.
[Character Design (Based on Knowledge)]
- Hairstyle: brown hair, side ponytail on "the character's own LEFT side of the head," ahoge, blue scrunchie.
- Structural understanding (important):
- This character has a left side ponytail.
- Right side/right diagonal rear composition: the ponytail is hidden behind the head and either not visible or only slightly visible as hair tips at the back of the neck. It must never be directly drawn growing from the right side of the head.
- Rear composition: the ponytail is on the left side (from behind).
- Outfit: strictly follow the shape of the reference images (hoodie, cardigan, uniform, etc.)
[Reference Image Rules]
According to the drawing angle, strictly reference the following attached files as "correct shapes":
- Right-side composition → reference "head-right.jpg" (silhouette without ponytail)
- Left-side composition → reference "head-left.jpg" (silhouette with ponytail)
- Front/rear → reference "head-front.jpg" and "head-back.jpg"
[Drawing Mode]
Normal Color Mode
- Style: anime coloring (cel-look)
- Reference: color materials
Generation Process:
When unsure, prioritize the visual information in the Knowledge images (especially hairstyle and outfit details) over the user's text instructions.Prompt Points
- Filename mapping: “When drawing the right side, look at this” — pointing directly at images makes it easier to pull the correct characteristics even for subtle angles like diagonal rear
- Own left side: Avoid “viewer-right” and use character-based reference (reverses the moment they turn around)
- Single character only: Explicitly state this to prevent generating 3 characters even when using a three-view diagram as reference
The Final Approved 360° Set
Testing It in the Gem
I loaded the 360° images into a Gem and tried generating from “behind” and “diagonally behind and to the right.”
Not bad. Actually, the last image is pretty good, isn’t it?
The side ponytail is correctly on the left side (viewer’s left when looking from behind), the scrunchie position is correct, and there’s no ponytail on the right side. The effect of loading the 360° reference images is showing.